After i trace with debuggers tools.. i finally able to identify what might went wrong:
1. if you use Database Wizard, usually it will set Redirect Page (After Insert > Go to)... if there has value in it... remove it, it will make the MRT useless !
2. set the Foreign Key to main tableID with the session created by DataAssist. You can see the source code to know the session name... For my case: $WA_sessionName = "WADA_Insert_products"; then the session is WADA_Insert_products
3. you might set the redirect page from the MRT server behavior
The server behavior is works as expected although i admit it's not user friendly compare to ADDT Many-To-Many Triggers. But the positive side is you have more flexibility than ADDT offers.
End of Report.. Now Back to Work
