Alright, I'm making guesses here because I know basically nothing about mysql. My problem is that the published version of my "Forums" page holds two "General discussion" forums (one older, containing one post; and one more recent, without posts), whereas the draft version only holds one (the latter). This is the only one showing up in the CMS. This issue follows a number of removals of forums and forum holders, db/build flushes, and daily-build installations.

When navigating to the older forum I get the following notice at the top of the page:
Notice: Trying to get property of non-object in C:\www\forum\code\Forum.php on line 1824

So, something went wrong when deleting a forum holder, and the forum wasn't removed from the database?

What do I do to regain control of this page? Any help greatly appreciated.

Worked like a charm, thank you!