To clarify the two items I posted:
1) This isn't an issue with sliding forward, it is tilting. I'll take a video and post it later today.
2) I know for a fact this used to work on the passenger seat. You would lift the level on the passenger seat and the seat would fold forward and then slide forward (not electronically, but mechanically). Then when you'd manually fold it back it would also slide back in its original place. A friend of mine has a 330ci from the same year and his works as I described.