When I put the Helveticas back in the system folder, the problem disappeared.
It makes me wonder if being unable to run the combined updater is font related or if the installer is looking for something in the system that isn't there.
That sounds like the Combo problem disappeared?
Removing fonts from /
System/Library/Fonts could, indeed, affect your ability to run system updates.
Edit: Actually, messing with
anything in /System/Library has the potential to cause problems.