I fired up Photoshop CS2 today on a hunch, and sure enough, it starts and runs just barely well enough to test! When it starts, you have to dismiss a dialog box, press ^C in the console, and then dismiss another dialog box, but after that you can open an image, edit it, and save it successfully. Quite a few menu items misbehave, so there's lots left to do, but this is a lovely improvement.
It seems likely that Mikolaj's recent changes had something to do with this. He's been doing quite a bit on Photoshop lately. Go Mikolaj! - Dan