Auto increment Issue

Dear all,

 We have requirement to create dispatch plans for the contract orders.  Created a table call UsrDispatchPlan... In this table, I need auto increment number for UsrNumber field.

We are trying to create auto numbering for the 

We followed the below steps

1. Create system settings for UsrDispatchPlanCodeMask, UsrDispatchPlanLastNumber

2. I did not created a replacing module, since i am doing it for new requirement(table)

3. Created a process before saving with the below steps

        ->message start with message: UsrDispatchSaving

        ->ScriptTask "SetNumberGenerationParameter" with code:

              GenerateNumberUserTask.EntitySchema = Entity.Schema;

              return true;

        -> a user task "GenerateNumberUserTask", task type "Generate ordinal number ( Base )"

        -> as Script task "SetGeneratedNumber" with code :

                 Entity.SetColumnValue("UsrNumber", GenerateNumberUserTask.ResultCode);

                 return true;

4. Saved and published the process and object as well.

 But the code is not generated in the field. 

Same i did from client side.. It worked!!!! But I need to implement from server side.,.. Because Add option is given with the mini page, where i was not able to process the auto increment.

Even i tried to implement the auto increment with reference to the link.

https://community.bpmonline.com/questions/question-about-auto-numbering…

But did not work!!!. So i am trying to do it with server side.

Please help!!!!