Just my two cents, because I had a similar situation, so I'm not sure if you want to look into this as well.
I did a self-install of VWR springs, and when I finished and started up the car, I had what seemed like every imaginable error code pop up (ABS, headlights, etc.). In addition, my power steering was messed up (only noticeable at low speeds). Took it to a very reputable shop recommended to me by my local VW group and the guy ran a vag-com check on it.
Immediately found that I had nicked an ABS sensor on the front passenger side. Must have caught on something during the install and got torn. He soldered it for me to fix and the car was back to working perfectly.
Like I said, it might not be your specific issue, but since these cars rely on all these computers and sensors nowadays, any disconnected part of the circuit can cause a chain reaction of codes, so you might want to look into it. I was initially tempted to just clear the codes, but am glad I got it checked instead!