mbz.bmw

Hi everyone, I'm having a problem with my e60 and was hoping someone could help me out.
I bought this car a year ago with a bad motor. The car had 105k miles when i bought it but due to oil leaks and poor maintenance the engine blew. I replaced the motor and got it running and drove it out. Transmission was shifting well except for a weird gear transition in second gear, where it won't completely slip but it will feel like it wants to after it warms up. Then it goes through the rest of the gears normally. In order to correct that I tried unplugging the connector for the mechatronics and plugging it back in. After doing that, I also changed the nut for the gear shift selector on the side of the transmission. I took it out for a drive and it shifted fine until it warmed up again and it did the same thing in second gear. I got to a stop light and reached a full stop. I went to accelerate and the transmission completely disengaged. After giving it more throttle, it jumped back into gear and drove off. While driving, it jolted and slipped out of gear unless I floored the pedal where it jolted again and I got a warning light on the iDrive system. After that i pulled over and put it in park and shut it off. Started it back up, put it in drive and reverse and it refused to engage. It would rev pretty high but the car would not move. I plugged in my harbor freight obd scanner and got the following codes: p0700, p017e1, p017e4 and p017e5. I'm really unsure where to begin looking and what the problem could possibly be. Any help would be greatly appreciated.
Sorry for the long post here guys but just want to be very transparent in hopes of finding a solution.