sounds very similar to the problem i was (and still am) having. i did find that i needed to make sure I have admin rights to every single folder in that Autodesk support files folder where the pipe catalog was kept, otherwise, i couldn;t do squat.
i am having another problem with my road cataog, and i am thinking that the two issues might be stemming from the same underlying issue.
so my next step is to try a clean uninstall- a really clean uninstall including a registry scrub and probably switching over to my admin user instead of the other user i have on that machine then reinstalling.
as much as a PITA as an uninstall is, it is usually less PITA than fighting with this kind of thing.
my rule of thumb is always to submit the subscription support request- because a lot of the time they are great and helpful, and if they can't help you, you at least can take it to the next level and say "support couldn't help me" which shows you've taken some due diligence in using resources.
Support- Reseller-Discussion Group is usually a decent trifecta for finding some kind of answer or at least comiserators.
