Help with Cpvlab and Maxbounty subid updates

Hi, I've searched everywhere online but can't figure this out. I just set up cpvlab and i'm using it with maxbounty and linktrust. Linktrust has no problems updating my stats with conversion info using the callback pixel. I have set my callback in Maxbounty several different ways but it won't update the converting subids no matter what I try. I really dislike having to upload converting subids manually. Any tips? I found a couple tutorials online and I had everything exactly how they said even with the #S1#. I know I'm passing the cpvlab generated subids to Maxbounty but it seems the call back isn't passing them back.

I would appreciate if you have any suggestions.

Thanks!