New owner, HELP nothing works!!

[Spooner]

I just bought a 2002 X5, I just replaced the engine because original owner overheated old one. Everything worked great before disassembled. Now.. The power locks don't work, front wipers don't work, driver side mirror doesn't work, interior lights don't work, security alarm is always on so i unhooked it, self leveling suspension inact so it sits extremely low and rides terrible, central locking system doesn't work, power rear hatch doesn't work, and All the fuses are fine. It has a brand new alternator. Is it possible a ground isn't hooked up somewhere?? Someone please help who has a wiring diagram or something. I would appreciate any advice.. thanks, Eric