Hey... I encountered the same issue (quitting pssetup.app), albeit for a different reason:
Link (dyld) error:
Library not loaded: /sw/lib/libfreetype.6.dylib
Referenced from: /Applications/Games/Planeshift3D/pssetup.app/Contents/Resources/freefnt2.csbundle
Reason: image not found
Model: PowerMac8,2, BootROM 5.2.5f1, 1 processors, PowerPC G5 (3.0), 1.8 GHz, 1 GB
Graphics: ATI Radeon 9600, ATY,RV351, AGP, 128 MB
Just as FYI. The rest just works fine... got some bad FPS though (25-100), but then I am sitting in Asia.