If you follow the Mac News sites, you understand that Quark is a costly update (3.3r users regretted 4.0. until 4.11..then 5.0 caused numerous incompatibilities..then 5.01 updater wasted hours of troubleshooting --- "solution was to move your folder to desktop THEN update!" Who wrote that installer, should be shot...now Quark 6 doesn't save down to 4.x version, many XTensions need to be updated...)
A small, but known issue is if you run the update, you need the 6.0 CD. Then you must re-activate the updated version or run in demo mode. If you have both a workstation and portable, and you are permitted to install one version on both, installing the update will require calling Quark Support and getting new activation keys. Try this on a Friday night or Saturday afternoon, when your G5 powersupply blows chow and you need your laptop. Hold time was incredible...and what time is it in India?
Lesson: I'd think long and hard before updating and wait till confirmation that the updater DOES fix the program...or stick with 4.11 or 5.01 in Classic.