Well, I didn't find a forum here just for bugs.
I don't find anywhere in Reader's Help menu for reporting bugs.
I looked through this forum back into December and did not find a thread for Reader X bugs.
The 'registry hacks' thread didn't cover this particular bug, either.
In Edit -> Preferences, Internet section.
I have UNchecked both
Display PDF in browser
and
Allow fast web view
Saved, then shut down Reader...
But if I click on a PDF link on the web it still opens it in the browser instead of downloading to %temp% and opening in the standalone reader.
p.s. after signing up for an account here, new users are sent to
http://acrobatusers.com/membership/thanks?nocache=1
which notes that if there are validation problems to visit the support page, and the link given for that is http://acrobatusers.com/resources/support
But that link returns a 'page not found' error.
p.p.s. The 'tell us about your software' version picklist below this comment box does not let you choose Reader X, nor v10, either.