Failed to migrate Nintex Workflows, error: Guid should contain 32 digits with 4 dashes (4235639)

System.FormatException: Guid should contain 32 digits with 4 dashes (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx). at System.Guid.GuidResult.SetFailure(ParseFailureKind failure, String failureMessageID, Object failureMessageFormatArgument, String failureArgumentName, Exception innerException) at System.Guid.TryParseGuidWithDashes(String guidString, GuidResult& result) at System.Guid.TryParseGuid(String g, GuidStyles flags, GuidResult& result) at System.Guid..ctor(String g) at Metalogix.SharePoint.Actions.Migration.Nintex.PasteNintexWorkflow.ImportWorkflow(NintexWorkflowType type, SPWeb web, SPList list, String nwpFile) at Metalogix.SharePoint.Actions.Migration.Nintex.PasteNintexWorkflow.ImportWorkflowOperationLogging(SPNintexWorkflow source, SPWeb web, SPList list, LogItem nintexWorkflowoperation, String mappedNwpFile) at Metalogix.SharePoint.Actions.Migration.Nintex.PasteNintexWorkflow.MigrateWorkflow(SPNintexWorkflow source, SPWeb web, SPList list)