need help with transmission/mechanic

[ktnatlanta]

My 98 Contour transmission started shifting hard at about 62k. I had the transmission serviced but it did not get better. My mechanic said he couldn't get an error code. Finally, at 95K, the transmission died a horrible death and needed to be rebuilt. I made the mistake of going to an independent shop for the repairs. Now, $2,000 later (the mechanic was paid in cash the first time I picked up the car), the car goes (it would not when it was towed to the shop) but it still shifts hard when it warms up and the cruise control doesn't work (it did before the transmission quit). I've taken it back to the mechanic twice (so he's had three chances to fix it). At one point, my self-described "transmission expert" told me he couldn't get a mount for the car because it was a dealer-only part. At this point I don't have confidence in either his ability or intent to fix the car. Could someone tell me what's wrong with the stupid thing, so I can explain it to the expert? Or would I be better off getting Aamco to fix it and taking the expert to small claims court?