FQ Events - code calling standard function module not install specfic copy

I'm customizing the event 0030 by copying over the standard function module 'fkk_paymentrelease0030_new' over as a installation specific one. I made a Z_ copy of the above standard FM and assigned it to a custom Z* function group, gave it the same sequence # (0) as the above FM by maintaining the value in table TFKFBC and finally ensured that the copied FM is 'Active'. However, when I attempt to post via FPE1, I see that the standard FM is being called instead of my 'active' installation specific copy that I just created. What am I missing?