Sorry, my bad typing made things more confusing.
I can download the UT2003, and get the file ut2003-macosx-demo-2206.dmg onto my desktop
I can click on that, causing diskcopy to run, and successfully mount "Unreal tournament 2003 demo" on my desktop. The resultant icon looks like a little white zip drive or something.
Doubleclicking that icon causes all the desktop icons to disappear transiently, then reappear, but no program opens and no folder with the Unreal applicatioin appears.
This is a TiBook running 10.2.6. I recently had a replacement hard drive put in, courtesy of AppleCare, and all the system and application software was reinstalled cleanly in the last few weeks.
What should I do. I would like to try the demo...