diff --git a/Config/Entities/IParamsProvider.cs b/Config/Entities/IParamsProvider.cs
index 495a427ae..2df3de028 100644
--- a/Config/Entities/IParamsProvider.cs
+++ b/Config/Entities/IParamsProvider.cs
@@ -31,7 +31,7 @@ namespace Config.Entities
         /// Returns a list of possible values of one parameter (ComboBox when editing) or null (Textbox when editing).
         /// </summary>
         /// <param name="ix">Zero based index of the parameter</param>
-        IList<string> ParamValues(int ix);
+        ICollection<string> ParamValues(int ix);
 
 		/// <summary>
 		/// Returns a parameter value in the string form
diff --git a/TBF/BenchControl/Configs/ParamsProvider/ComponentCfgCtrl.cs b/TBF/BenchControl/Configs/ParamsProvider/ComponentCfgCtrl.cs
index 4318fd111..4bb1074e4 100644
--- a/TBF/BenchControl/Configs/ParamsProvider/ComponentCfgCtrl.cs
+++ b/TBF/BenchControl/Configs/ParamsProvider/ComponentCfgCtrl.cs
@@ -62,7 +62,7 @@ namespace TBF.BenchControl.Configs.ParamsProvider
             editors = new Control[paramsProvider.ParamsCount()];
             for (int i = 0; i < paramsProvider.ParamsCount(); i++)
             {
-                IList<string> values = paramsProvider.ParamValues(i);
+                ICollection<string> values = paramsProvider.ParamValues(i);
                 if (values == null)
                 {
                     editors[i] = new TextBox();
diff --git a/TBF/BenchControl/DataContainers/BackupAndSecurityOptions/ComponentCfg.cs b/TBF/BenchControl/DataContainers/BackupAndSecurityOptions/ComponentCfg.cs
index 53777d178..e58c57992 100644
--- a/TBF/BenchControl/DataContainers/BackupAndSecurityOptions/ComponentCfg.cs
+++ b/TBF/BenchControl/DataContainers/BackupAndSecurityOptions/ComponentCfg.cs
@@ -53,7 +53,7 @@ namespace TBF.BenchControl.DataContainers.BackupAndSecurityOptions
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             return null;
         }
diff --git a/TBF/BenchControl/DataContainers/BenchInfo/Extended/ComponentCfg.cs b/TBF/BenchControl/DataContainers/BenchInfo/Extended/ComponentCfg.cs
index 0f9ca42f5..c8407960a 100644
--- a/TBF/BenchControl/DataContainers/BenchInfo/Extended/ComponentCfg.cs
+++ b/TBF/BenchControl/DataContainers/BenchInfo/Extended/ComponentCfg.cs
@@ -83,7 +83,7 @@ namespace TBF.BenchControl.DataContainers.BenchInfo.Extended
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             if (i == 10)
             {
diff --git a/TBF/BenchControl/DataContainers/BenchInfo/iPerl/ComponentCfg.cs b/TBF/BenchControl/DataContainers/BenchInfo/iPerl/ComponentCfg.cs
index b6d9e56b0..a290f2819 100644
--- a/TBF/BenchControl/DataContainers/BenchInfo/iPerl/ComponentCfg.cs
+++ b/TBF/BenchControl/DataContainers/BenchInfo/iPerl/ComponentCfg.cs
@@ -111,7 +111,7 @@ namespace TBF.BenchControl.DataContainers.BenchInfo.iPerl
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             if (i == 10)
             {
diff --git a/TBF/BenchControl/DataContainers/Buoyancy/ComponentCfg.cs b/TBF/BenchControl/DataContainers/Buoyancy/ComponentCfg.cs
index e3d83c5bd..6ab44396b 100644
--- a/TBF/BenchControl/DataContainers/Buoyancy/ComponentCfg.cs
+++ b/TBF/BenchControl/DataContainers/Buoyancy/ComponentCfg.cs
@@ -71,7 +71,7 @@ namespace TBF.BenchControl.DataContainers.Buoyancy
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             return null;
         }
diff --git a/TBF/BenchControl/DataContainers/Density/ComponentCfg.cs b/TBF/BenchControl/DataContainers/Density/ComponentCfg.cs
index 231aef355..de4dc7a06 100644
--- a/TBF/BenchControl/DataContainers/Density/ComponentCfg.cs
+++ b/TBF/BenchControl/DataContainers/Density/ComponentCfg.cs
@@ -74,7 +74,7 @@ namespace TBF.BenchControl.DataContainers.Density
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             return null;
         }
diff --git a/TBF/BenchControl/DataEntry/DataStream/EntryFormCfg.cs b/TBF/BenchControl/DataEntry/DataStream/EntryFormCfg.cs
index 03cb271a5..246d40899 100644
--- a/TBF/BenchControl/DataEntry/DataStream/EntryFormCfg.cs
+++ b/TBF/BenchControl/DataEntry/DataStream/EntryFormCfg.cs
@@ -57,7 +57,7 @@ namespace TBF.BenchControl.DataEntry.DataStream
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             switch (i)
             {
diff --git a/TBF/BenchControl/Elde/TempMeterMeret/TempMeterCfg.cs b/TBF/BenchControl/Elde/TempMeterMeret/TempMeterCfg.cs
index 89a9426a3..6871dd1d6 100644
--- a/TBF/BenchControl/Elde/TempMeterMeret/TempMeterCfg.cs
+++ b/TBF/BenchControl/Elde/TempMeterMeret/TempMeterCfg.cs
@@ -96,7 +96,7 @@ namespace TBF.BenchControl.Elde.TempMeterMeret
         };
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
-        public IList<string> ParamValues(int i) { return null; }
+        public ICollection<string> ParamValues(int i) { return null; }
 
         public string ToString(int i)
         {
diff --git a/TBF/BenchControl/Hart/Common/HartCfg.cs b/TBF/BenchControl/Hart/Common/HartCfg.cs
index a76612fa4..bc2fec652 100644
--- a/TBF/BenchControl/Hart/Common/HartCfg.cs
+++ b/TBF/BenchControl/Hart/Common/HartCfg.cs
@@ -74,7 +74,7 @@ namespace TBF.BenchControl.Hart.Common
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             IList<string> list = new List<string>();
             switch (i)
diff --git a/TBF/BenchControl/Hart/Nivotrack/NivotrackCfg.cs b/TBF/BenchControl/Hart/Nivotrack/NivotrackCfg.cs
index a3e39c943..0d684dbd1 100644
--- a/TBF/BenchControl/Hart/Nivotrack/NivotrackCfg.cs
+++ b/TBF/BenchControl/Hart/Nivotrack/NivotrackCfg.cs
@@ -86,7 +86,7 @@ namespace TBF.BenchControl.Hart.Nivotrack
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             IList<string> list = new List<string>();
             switch (i)
diff --git a/TBF/BenchControl/Modbus/UltrasoundLevelMeter/LevelMeterCfg.cs b/TBF/BenchControl/Modbus/UltrasoundLevelMeter/LevelMeterCfg.cs
index c8d86a9b8..75a42fefc 100644
--- a/TBF/BenchControl/Modbus/UltrasoundLevelMeter/LevelMeterCfg.cs
+++ b/TBF/BenchControl/Modbus/UltrasoundLevelMeter/LevelMeterCfg.cs
@@ -65,7 +65,7 @@ namespace TBF.BenchControl.Modbus.UltrasoundLevelMeter
         };
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
-        public IList<string> ParamValues(int i) { return null; }
+        public ICollection<string> ParamValues(int i) { return null; }
 
 		public string ToString(int i)
 		{
diff --git a/TBF/BenchControl/Modbus/WaterAnalyzer/AnalyzerCfg.cs b/TBF/BenchControl/Modbus/WaterAnalyzer/AnalyzerCfg.cs
index d5c47c041..b89dbeb4c 100644
--- a/TBF/BenchControl/Modbus/WaterAnalyzer/AnalyzerCfg.cs
+++ b/TBF/BenchControl/Modbus/WaterAnalyzer/AnalyzerCfg.cs
@@ -66,7 +66,7 @@ namespace TBF.BenchControl.Modbus.WaterAnalyzer
         };
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
-        public IList<string> ParamValues(int i) { return null; }
+        public ICollection<string> ParamValues(int i) { return null; }
 
 		public string ToString(int i)
 		{
diff --git a/TBF/BenchControl/Modbus/WaterAnalyzer2/AnalyzerCfg.cs b/TBF/BenchControl/Modbus/WaterAnalyzer2/AnalyzerCfg.cs
index 13c26011b..a005ff728 100644
--- a/TBF/BenchControl/Modbus/WaterAnalyzer2/AnalyzerCfg.cs
+++ b/TBF/BenchControl/Modbus/WaterAnalyzer2/AnalyzerCfg.cs
@@ -72,7 +72,7 @@ namespace TBF.BenchControl.Modbus.WaterAnalyzer2
         };
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
-        public IList<string> ParamValues(int i) { return null; }
+        public ICollection<string> ParamValues(int i) { return null; }
 
 		public string ToString(int i)
 		{
diff --git a/TBF/BenchControl/Output/DB/SensusOracle/ProcedureParams.cs b/TBF/BenchControl/Output/DB/SensusOracle/ProcedureParams.cs
index b21a75cce..032358ca1 100644
--- a/TBF/BenchControl/Output/DB/SensusOracle/ProcedureParams.cs
+++ b/TBF/BenchControl/Output/DB/SensusOracle/ProcedureParams.cs
@@ -63,7 +63,7 @@ namespace TBF.BenchControl.Output.DB.SensusOracle
 		public override string ParamName(int i) { return paramNames[i]; }
 		public override int ParamsCount() { return paramNames.Length; }
 
-        public override IList<string> ParamValues(int i)
+        public override ICollection<string> ParamValues(int i)
         {
             IList<string> retVal = new List<string>();
 
diff --git a/TBF/BenchControl/Output/EventTriggers/Iperl/TriggerCfg.cs b/TBF/BenchControl/Output/EventTriggers/Iperl/TriggerCfg.cs
index 918712917..4554a5367 100644
--- a/TBF/BenchControl/Output/EventTriggers/Iperl/TriggerCfg.cs
+++ b/TBF/BenchControl/Output/EventTriggers/Iperl/TriggerCfg.cs
@@ -60,7 +60,7 @@ namespace TBF.BenchControl.Output.EventTriggers.Iperl
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             IList<string> listOfValues = new List<string>();
             if (i == 1)
diff --git a/TBF/BenchControl/Output/EventTriggers/Standard/TriggerCfg.cs b/TBF/BenchControl/Output/EventTriggers/Standard/TriggerCfg.cs
index 6dee3b5b5..7e279e2b5 100644
--- a/TBF/BenchControl/Output/EventTriggers/Standard/TriggerCfg.cs
+++ b/TBF/BenchControl/Output/EventTriggers/Standard/TriggerCfg.cs
@@ -168,7 +168,7 @@ namespace TBF.BenchControl.Output.EventTriggers.Standard
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             IList<string> listOfValues = new List<string>();
             if (i >= 12)
diff --git a/TBF/BenchControl/Output/FileWriters/IperlLogger/WriterCfg.cs b/TBF/BenchControl/Output/FileWriters/IperlLogger/WriterCfg.cs
index 4627ba838..ee4044191 100644
--- a/TBF/BenchControl/Output/FileWriters/IperlLogger/WriterCfg.cs
+++ b/TBF/BenchControl/Output/FileWriters/IperlLogger/WriterCfg.cs
@@ -57,7 +57,7 @@ namespace TBF.BenchControl.Output.FileWriters.IperlLogger
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             switch (i)
             {
diff --git a/TBF/BenchControl/ProcedureParamsBase.cs b/TBF/BenchControl/ProcedureParamsBase.cs
index 399cc141b..aa9157d87 100644
--- a/TBF/BenchControl/ProcedureParamsBase.cs
+++ b/TBF/BenchControl/ProcedureParamsBase.cs
@@ -36,7 +36,7 @@ namespace TBF.BenchControl
 		}
 
         /// <summary> To be overridden </summary>
-        public virtual IList<string> ParamValues(int ix)
+        public virtual ICollection<string> ParamValues(int ix)
         {
             return null;
         }
diff --git a/TBF/BenchControl/RegisterReaders/DataStream/MefImport/MefImportCfg.cs b/TBF/BenchControl/RegisterReaders/DataStream/MefImport/MefImportCfg.cs
index 8dfb5bbb1..5c8e5b82a 100644
--- a/TBF/BenchControl/RegisterReaders/DataStream/MefImport/MefImportCfg.cs
+++ b/TBF/BenchControl/RegisterReaders/DataStream/MefImport/MefImportCfg.cs
@@ -51,7 +51,7 @@ namespace TBF.BenchControl.RegisterReaders.DataStream.MefImport
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             switch (i)
             {
diff --git a/TBF/BenchControl/RegisterReaders/DataStream/Reader/ReaderCfg.cs b/TBF/BenchControl/RegisterReaders/DataStream/Reader/ReaderCfg.cs
index 748250b32..53cc89284 100644
--- a/TBF/BenchControl/RegisterReaders/DataStream/Reader/ReaderCfg.cs
+++ b/TBF/BenchControl/RegisterReaders/DataStream/Reader/ReaderCfg.cs
@@ -57,7 +57,7 @@ namespace TBF.BenchControl.RegisterReaders.DataStream.Reader
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             switch (i)
             {
diff --git a/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationParams.cs b/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationParams.cs
index 985e8f6f6..20b427358 100644
--- a/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationParams.cs
+++ b/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationParams.cs
@@ -38,12 +38,11 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
 		public override string ParamName(int i) { return paramNames[i]; }
 		public override int ParamsCount() { return paramNames.Length; }
 
-        public override IList<string> ParamValues(int i)
+        public override ICollection<string> ParamValues(int i)
         {
-            IList<string> retVal = new List<string>();
-
             if (i == 0)
             {
+                List<string> retVal = new List<string>();
                 retVal.Add(iPerlCommunicationForm.ReadConfigurationStr);
                 retVal.Add(string.Format("{0} A0", iPerlCommunicationForm.SetTestModeStr));
                 retVal.Add(string.Format("{0} A4", iPerlCommunicationForm.SetTestModeStr));
@@ -81,14 +80,12 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
                 retVal.Add(string.Format("{0} if enabled", iPerlCommunicationForm.ReadConfigurationStr));
                 retVal.Add(string.Format("{0} 80", iPerlCommunicationForm.SetTestModeStr));
                 retVal.Add("iPerl_check prevWorkStep direction q2factors");
+                return retVal;
             }
             else
             {
-                retVal.Add(Strings.yes);
-                retVal.Add(Strings.no);
+                return new string[] { Strings.yes, Strings.no };
             }
-
-            return retVal;
         }
 
 		public override string ToString(int i)
diff --git a/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlHead/ProcParams.cs b/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlHead/ProcParams.cs
index 542f52cd3..1ac452167 100644
--- a/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlHead/ProcParams.cs
+++ b/TBF/BenchControl/TestMethods/iPerlCommunication/iPerlHead/ProcParams.cs
@@ -54,7 +54,7 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication.iPerlHead
 		public override string ParamName(int i) { return paramNames[i]; }
         public override int ParamsCount() { return paramNames.Length; }
 
-        public override IList<string> ParamValues(int i)
+        public override ICollection<string> ParamValues(int i)
         {
             if (i == 0)
             {
diff --git a/TBF/BenchControl/TestParamsBase.cs b/TBF/BenchControl/TestParamsBase.cs
index db0183355..34b868e8c 100644
--- a/TBF/BenchControl/TestParamsBase.cs
+++ b/TBF/BenchControl/TestParamsBase.cs
@@ -36,7 +36,7 @@ namespace TBF.BenchControl
 		}
 
         /// <summary> To be overridden </summary>
-        public virtual IList<string> ParamValues(int ix)
+        public virtual ICollection<string> ParamValues(int ix)
         {
             return null;
         }
diff --git a/TBF/BenchControl/Various/ErrorFlags/ErrorsCfg.cs b/TBF/BenchControl/Various/ErrorFlags/ErrorsCfg.cs
index 166366cd9..bf6926224 100644
--- a/TBF/BenchControl/Various/ErrorFlags/ErrorsCfg.cs
+++ b/TBF/BenchControl/Various/ErrorFlags/ErrorsCfg.cs
@@ -62,7 +62,7 @@ namespace TBF.BenchControl.Various.ErrorFlags
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             return null;
         }
diff --git a/TBF/BenchControl/Various/StatisticsMonitoring/StatisticsCfg.cs b/TBF/BenchControl/Various/StatisticsMonitoring/StatisticsCfg.cs
index 29861a066..a372b1333 100644
--- a/TBF/BenchControl/Various/StatisticsMonitoring/StatisticsCfg.cs
+++ b/TBF/BenchControl/Various/StatisticsMonitoring/StatisticsCfg.cs
@@ -54,7 +54,7 @@ namespace TBF.BenchControl.Various.StatisticsMonitoring
         public string ParamName(int i) { return paramNames[i]; }
         public int ParamsCount() { return paramNames.Length; }
 
-        public IList<string> ParamValues(int i)
+        public ICollection<string> ParamValues(int i)
         {
             return null;
         }
diff --git a/TBF/UI/Procedures/ProcedureParamsCtrl.cs b/TBF/UI/Procedures/ProcedureParamsCtrl.cs
index 8bafe5d5d..7318475e9 100644
--- a/TBF/UI/Procedures/ProcedureParamsCtrl.cs
+++ b/TBF/UI/Procedures/ProcedureParamsCtrl.cs
@@ -96,7 +96,7 @@ namespace TBF.UI.Procedures
                 for (int i = 0; i < paramsCount; i++)
                 {
                     listViewEx.Columns.Add(sampleToCreateHeader.ParamName(i), 80);
-                    IList<string> values = sampleToCreateHeader.ParamValues(i);
+                    ICollection<string> values = sampleToCreateHeader.ParamValues(i);
                     if (values == null)
                     {
                         editors[i] = new TextBox();
diff --git a/TBF/UI/Procedures/ProcedureParamsMixedCtrl.cs b/TBF/UI/Procedures/ProcedureParamsMixedCtrl.cs
index 7ce2c25bf..c7ca11fa7 100644
--- a/TBF/UI/Procedures/ProcedureParamsMixedCtrl.cs
+++ b/TBF/UI/Procedures/ProcedureParamsMixedCtrl.cs
@@ -87,7 +87,7 @@ namespace TBF.UI.Procedures
                 k++;
                 for (int j = 0; j < paramCounts[i]; j++)
                 {
-                    IList<string> values = cmpntsParams[i].ParamValues(j);
+                    ICollection<string> values = cmpntsParams[i].ParamValues(j);
                     if (values == null)
                     {
                         editors[k] = new TextBox();
diff --git a/TBF/UI/Procedures/TestParamsCtrl.cs b/TBF/UI/Procedures/TestParamsCtrl.cs
index 499471e80..907f12ca9 100644
--- a/TBF/UI/Procedures/TestParamsCtrl.cs
+++ b/TBF/UI/Procedures/TestParamsCtrl.cs
@@ -81,7 +81,7 @@ namespace TBF.UI.Procedures
                 for (int i = 0; i < paramsCount; i++)
                 {
                     listViewEx.Columns.Add(sampleToCreateHeader.ParamName(i), 90);
-                    IList<string> values = sampleToCreateHeader.ParamValues(i);
+                    ICollection<string> values = sampleToCreateHeader.ParamValues(i);
                     if (values == null)
                     {
                         editors[i] = new TextBox();