[Chicks-Love-Bimmers]

I'm currently running catless downpipes/exhaust and have Procede and BMS DP Fix, I don't think the harness for the Procede has been modified yet, I got it from someone else and it was Rev 2 V4 back then. I don't have a BT tool and from what I understand, you have to read the codes before adjusting the DP fix. Is this step absolutely crucial, will I not pass if I throw the wrong code? Should I leave the Procede in and try to install the DP fix on the harness? If I do, do I just leave it on map 0?