Just a note here about the technical aspects of the 2GB memory barrier and 32bit applications (it's the only thing i can speak of here - i know zilch about modeling).
Large Address Aware (LAA - common terminology) 32bit applications actually get their virtual space extended to 4GB when executed on a 64bit OS (under Windows).
I've never looked at the source for OpenZone so I don't even know which language it is written in, but making the application large address aware is a trivial matter as long as the memory addressing remains sane.
Here's a discussion on this I found with Google:
http://www.wintellect.com/CS/blogs/j...ressaware.aspx
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