Webclient is not able proceed custom manufacturing process

Hello,

in our company database we have new module for posting manufacture. RTC is working perfect with no problems, but when I try make exactly the same in webclient DynamicsNav service crush and I get blue screen with error occured. 

From event viewer I get this:

Type: Microsoft.Dynamics.Nav.Types.Exceptions.NavPageCloseRequestException
Message:
StackTrace:
   at Microsoft.Dynamics.Nav.Client.UIPatterns.FormCloseRequestPattern.DataAccess_FormCloseRequest(Object sender, NavFormCloseRequestEventArgs e)
   at Microsoft.Dynamics.Nav.Client.DataBinder.FormCloseRequestHandler.NotifyFormCloseRequest(Guid serverFormHandle, Boolean isClientRequest)
   at Microsoft.Dynamics.Nav.Client.DataBinder.NstDataAccess.CompleteOperation(OperationContext operation, Boolean save, Boolean performFormUpdate)
   at Microsoft.Dynamics.Nav.Client.DataBinder.OperationContext.CompleteOperationCore()
   at Microsoft.Dynamics.Nav.Client.DataBinder.DataAccessOperationContext.DisposeCore()
   at Microsoft.Dynamics.Nav.Client.DataBinder.OperationContext.Dispose()
   at Microsoft.Dynamics.Nav.Client.DataBinder.NstDataAccess.InvokeOnNewRecord(NavRecord record, NavRecord xrec, NavRecordState state, Object[] args)
   at Microsoft.Dynamics.Nav.Client.DataBinder.NstDataAccess.OnNewRecord(Boolean clearFormState, NavRecord xrec, Object[] args)
   at Microsoft.Dynamics.Nav.Client.DataBinder.NavBindingManager.EnsureOnNewRecordIsUpToDate()
   at Microsoft.Dynamics.Nav.Client.DataBinder.NavBindingManager.OnCurrentRowChanged(CurrentRowChangeEventArgs e)
   at Microsoft.Dynamics.Framework.UI.BindingManager.set_CurrentCollectionIndex(Int32 value)
   at Microsoft.Dynamics.Framework.UI.VirtualRows.UpdateAfterInsert(Int32 index, Boolean needsUpdateCurrentRow)
   at Microsoft.Dynamics.Framework.UI.VirtualRows.AddWithoutValidation(RowEntry row, Boolean needsUpdateCall, Boolean needsUpdateCurrentRow, Boolean insertFirst, Boolean raiseEvents)
   at Microsoft.Dynamics.Framework.UI.VirtualRows.Add(RowEntry row)
   at Microsoft.Dynamics.Nav.Client.UIPatterns.DraftLinePattern.AddDraftRow()
   at System.ComponentModel.PropertyChangedEventHandler.Invoke(Object sender, PropertyChangedEventArgs e)
   at Microsoft.Dynamics.Framework.UI.BindingManager.RaiseEventsForInvalidatedProperties()
   at Microsoft.Dynamics.Framework.UI.BindingManager.DoFill(DataReaderFillOptions fillOptions)
   at Microsoft.Dynamics.Framework.UI.BindingManager.Fill(BindingManagerFillOptions options)
   at Microsoft.Dynamics.Framework.UI.LogicalForm.LoadDataInternal()
   at Microsoft.Dynamics.Framework.UI.LogicalForm.LoadData()
   at Microsoft.Dynamics.Framework.UI.LogicalOperationInvoker.LoadData(LogicalForm form)
   at Microsoft.Dynamics.Framework.UI.LogicalOperationInvoker.<>c__DisplayClass29_0.<UISession_DialogToShow>b__0()
   at Microsoft.Dynamics.Framework.UI.LogicalOperationInvoker.InvokeAndHandleExceptions(Func`1 action, IExceptionHandler exceptionHandler)
Source: Microsoft.Dynamics.Nav.Client.UI

I have no idea how to fix it. Please do you have some advices or experiences to share?

Thank you.