2002 Kia spectra transmission nightmare. PLEASE HELP?

Okay. first things first. About a week ago, the car started driving odd. It would feel like it wouldn't go past 3rd gear, even at 60mph.... I could get it to switch into the next gear by gunning it a little bit, then it would go up as it wound down a bit. Then, a few days ago, I was coming home from work and got on the toll road and noticed that it was NOT coming out of 3rd gear at all. Then the check engine light came on. I knew to immediately get off the highway and take slower side roads. I got to an Autozone, had the codes read and checked the transmission fluid levels. The codes were p1529 and p0763, which were "solenoid c electrical problem" and the standard code for the transmission to get the engine light to come on. So, I took it to a transmission shop to get diagnosed. they said solenoid replacement for $400. Trying to save money and help a friend out (first mistake) we let a friend do it. First mishap, he THOUGHT he checked the solenoid c and said it was fine, cleaned out the filter, etc, etc.... Went to drive it a short while later (after he left of course - second mistake) and it was doing the same thing. On to the next day... He came back, took it apart more, then realized he hadn't checked the solenoid C at all. He hadn't even pulled that one out in the first place! So, off to the transmission parts place and bought the full kit, with all new solenoids. Next day.... He comes back, pulls the full valve body out and checks the correct solenoid and lo and behold, it was bad!! Then of course, being Murphy's law, the kit he had bought on FRIDAY was the wrong one and the transmission parts place was closed as now it's Saturday. A solenoid is hard to find for a Kia on a Saturday, so off to the junkyard we go to get a whole new (to us) valve body and installed it. All seemed well til we took it for a spin. Now, it won't come out of drive. Won't go into reverse, won't go into park. We had to turn it off to put it in neutral and back it out of the auto parts lot (we checked the fluid levels). It will go into park, but only as it's still rev ving. now, we're at a loss. the guy who "fixed" it is now saying it's the computer and we can get a $30 part to bypass something or another. I wouldn't hear it. I told him there is no way that's what it is. And basically made sure he left the old valve body and parts and told him to go. Now, what in the heck are we going to do?? A friend says that he should have never touched the solenoids with bare hands, which he did. I am frustrated and at my wits ends.... I don't have a lot of money to put into a $2500 car. Is there anyone out there who might have come across something similar? Please?!?!