Brad - thanks for the great port. Being a developer myself (not games though) I have some insight into what you've been through - take a good long break
Some insight the Win side - I was able to get this running on 4 of my PCs for net play:
It plays great on my Dell 9300 with a 256MB nVidia 6800 go card
It also plays perfectly on my primary desktop: A64 3200+ Radeon 9800 128MB
It plays with some very minor glitching on my file server (Athlon 2500+, Radeon 8500 AIW 128MB)
It plays acceptably, but slow and in low resolution on my daughter's dell 700M which is ~1.7 Ghz, 64MB shared Intel onboard graphics (and it's not the 950 which is a better chipset).
So, from that insight, I'd think that it *could* work on the integrated graphics intel machines, such as the mini or the MacBook. I'd also think that a G4 with a 9800 or even 9600XT should be capable.
Just my 0.02. I'm looking forward to trying it on the Mac side, my work is finally getting me my first Mac in a long time (since OS 8, yike!

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