Mainly if a mac user main reasons are anything that is outputted and beach ball starts spinning, then programme is prevented from completing operations due to bugs in software and has nothing to do with your operating system.
Bug reports are useless because although Quark receive them, they haven't a clue in how to act on.
However some actions can be altered using Terminal if you know how this works, also as mentioned by others clean install with all preferences relating to quark, also with printers you need to reinstall pdds after Quark is installed to recognise them. Although quark uses the its ppd manager this doesn't always work best and causes crashes when outputting. Programs are available to help do complete uninstall on web and also running OnyX can help.
Above all if you continue with Quark get all patches updated.
Having worked with quark software for ten years this release is the worst they have produced.
Try before you buy!!!!