I hope this isn't a egg sucking lesson for granny. 1) Do a compression check again and get some numbers. They should all be 120psi minimum. If not see your wrench with a writ. 2) Pull off start wire from starter motor, join a gauge to the fuel rail(s) and get a mate to hold the key in P3 (start). The pump(s) will run and give you a pressure reading. If you are about 40psi it's good. If not see your wrench with another writ. 3) Pull a plug wire (or coil pack) reconnect starter wire and check for spark when engine turning over. If you have a spark then it's a basic timing issue - cam and sensors out of sync. If no spark it's either crank sensor problems or EWS related. Could be as simple as recoding a key, multi-plug half out, blown fuse, blown relay, bad sensor or even no fuel (Yes I got caught). If it's the EWS box then I won't even pretend I can fix that!!
Good - Fast - Cheap: Pick any two.
E23 735i; E30 318i; E32 735iL (X 2 - 1 Alpine White and 1 Glacier Blue); E34 535i; E38 735iL; R50 Cooper; R55 Cooper Clubman.
E21 318i; E32 735iL; E34 535i; E38 730iL; E53 4.4i