Steps to reproduce:

Load the test attached internally in a project and double click to open it.

Expected behavior: To be able to open the test successfully.

Actual behavior: An error is prompted and the following is output in the log:

[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11)] First trace message from pool unnamed thread (managed ID = 11, native ID = 20408).
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] SerializerService.<GetSettings>b__2() : Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] SerializerService.<GetSettings>b__2() : Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] SerializerService.<GetSettings>b__2() : Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] SerializerService.<GetSettings>b__2() : Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] SerializerService.<GetSettings>b__2() : Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
[10/22 09:08:48,Telerik.TestStudio.Desktop.exe(28696:11),ProjectModel] TestFileHandler.LoadFromDisk() : EXCEPTION! (see below)
     Situation: Unable to load test 'C:\Users\ittodorov\Documents\Test Studio Projects\October2015\Ca_CheckCostComponentSplitInSiPa_CostComponentSplitInSiPaWorks_EN.tstest'
     Outer Exception Type: Newtonsoft.Json.JsonSerializationException
     Message: Error setting value to 'Comparison' on 'ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.GeneralPropertyVerificationDescriptor'.
     HRESULT: 0x80131500 (Official ID (if app.) = COR_E_EXCEPTION, Error Bit = FAILED, Facility = FACILITY_URT, Code = 5376)
     Call Stack:
          at Newtonsoft.Json.Serialization.DynamicValueProvider.SetValue(Object target, Object value)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Populate(JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerProxy.PopulateInternal(JsonReader reader, Object target)
          at ArtOfTest.Common.Serialization.JsonKnownTypeConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Populate(JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerProxy.PopulateInternal(JsonReader reader, Object target)
          at ArtOfTest.Common.Serialization.JsonKnownTypeConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateList(IList list, JsonReader reader, JsonArrayContract contract, JsonProperty containerProperty, String id)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Populate(JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerProxy.PopulateInternal(JsonReader reader, Object target)
          at ArtOfTest.Common.Serialization.JsonKnownTypeConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Populate(JsonReader reader, Object target)
          at Newtonsoft.Json.Serialization.JsonSerializerProxy.PopulateInternal(JsonReader reader, Object target)
          at ArtOfTest.Common.Serialization.JsonKnownTypeConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
          at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
          at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)
          at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)
          at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)
          at ArtOfTest.Common.Design.SerializerService.DeserializeFromJSON[T](String serializedObject, Boolean autoLoadTypesFromAssemblies)
          at ArtOfTest.WebAii.Design.ProjectModel.TestFileHandler.LoadFromJSON(String rawFileText, Boolean autoLoadTypes)
          at ArtOfTest.WebAii.Design.ProjectModel.TestFileHandler.LoadFromDisk(String pathToFile, Boolean autoLoadTypes, FileOpenResult& result)

     Inner Exception Type: System.ArgumentException
     Message: Value does not fall within the expected range.
     HRESULT: 0x80070057 (Official ID (if app.) = E_INVALIDARG, Error Bit = FAILED, Facility = FACILITY_WIN32, Code = ERROR_INVALID_PARAMETER)
     Call Stack:
          at ArtOfTest.WebAii.Design.IntrinsicTranslators.Silverlight.Descriptors.PropertyVerificationDescriptor.set_Comparison(String value)
          at SetComparison(Object , Object )
          at Newtonsoft.Json.Serialization.DynamicValueProvider.SetValue(Object target, Object value)

[10/22 09:08:50,Telerik.TestStudio.Desktop.exe(28696:11),TestStudio] TestsProvider.UpdateItem() : EXCEPTION! (see below)
     Outer Exception Type: System.NullReferenceException
     Message: Object reference not set to an instance of an object.
     HRESULT: 0x80004003 (Official ID (if app.) = E_POINTER, Error Bit = FAILED, Facility = FACILITY_NULL, Code = 16387)
     Call Stack:
          at ArtOfTest.WebAii.Design.ProjectModel.Providers.TestsProvider.UpdateItem(TestBase item)

Reproduced with Test Studio 2015.3.1015