Ok I've been reading this thread and recalling this map for a while now, and I do agree that those impossible areas need fixing, unless you're really really into "D-Day on Omaha Beach" type scenarios.
You should also get rid of that kill zone so that I can jump off the roof when we are finally all done.
I also rather like the idea of the hellfire flak cannon being added to the map. Perhaps half way up building one?
Don't be surprised if it takes a long while to find a good final version of the tweaked map. It took the mappers and play testers over at Excalibur about a year to get Long Corridor 2006 ready for release, if I remember correctly.