1995 540i ran out of gas now won't start

Get ready for this one. Ran out of gas on an "angled" driveway. Put two gallons in, wouldn't start. Put 2 more in, wouldn't start. Put 2 more in still won't start. Hicupped a little along the way but never stayed started. Fuel pump fine. Checked pressure (pumping about 42psi). Put starter fluid in intake manifold, engine backfired and blew off the back of the intake manifold. Needed to replace the PCV anyway. Replaced. Still won't start. Backfire of starter fluid in intake manifold indicates spark during open intake valve cycle. Spoke with expert BMW specialists from Austria and he said engine timing change not possible with this engine, but this is what has happened ("sounds" like the timing is off too). Not sure why, but somehow there has been permanent damage to some engine component caused by running out of gas!!? Very strange. Any input? Thanks in advance.

Starting fluid causing a backfire sucks, but it happens. That stuff is extreamly flammable. the good news is, you have spark.
Is there a check engine light on ?
You are getting 42psi going into the fuel rail ?? What about coming out of the fuel rail ?? May sound weird, but just to make sure fuel is getting returned to the tank. I had a fuel pump issue, and it caused 2 of my fuel injectors to go bad, but that also gave me a CEL.
If you are SURE the fuel delivery is good, something else to check maybe the crank position sensor. When mine went bad, sometimes it "almost" started, sometimes nothing.
One more thing i really hate to admit----- I actually crossed the return and supply of the fuel lines while trying to diagnose the CPS.
Just throwing ideas out there for you.