Are you saying you lost functionality that you already had before the upgrade? Or are you using a PUC (device model selected in the Avant menu) that was added with the software upgrade to control your Motorola but it doesn't work very well? Don't know that model but there aren't too many options for the Avant:
1. Try some other PUCs to see if they work better.
2. Talk your dealer into restoring it to the working condition (Assuming you had had control previously.)
3. Try the Beo5 remote so you can program/have programmed to work however you want with the DVR.