722.6 Awkward Downshifts

[6.3basketcase]

Help! I recently aquired a 1998 E320 4-matic wagon with a transmission problem. The car has 70K miles and when downshifting to an incomplete stop it hesitates and/or clunks hard into second gear. The previous owner recently had a $500 "on vehicle repair" by an independent shop that reportedly made the problem less acute. What do you guys think is causing this? I am a pretty good mechanic, but clueless about these electronic transmissions. By the way, is the 722.6 similar to the ZF model 5HP24?

David R.