I don't know if I'm covering old ground here but...the black load screen issue with Vista 64bit / 4 gb RAM - The ONLY way I can get the game to run is by dropping back my nvidia driver to version 1.54. I tried all afternoon with various "fixes" (including -maxmem=256), removing sticks of RAM etc etc. If anybody else is still struggling with this one - just use the older nvidia driver - it works! PLEASE let's turn the heat on nvidia to produce a fix!!!
Quad core G0 stepping CPU 2.4Ghz (no o/c)
4GB ballistix RAM
Vista ultimate 64 bit