Just adding my two cents to say that this bug is absolutely driving me batty and I'm experiencing all the issues everyone else is describing - mouseover tips not working, listboxes not scrolling, mouse-over-terrain not working.
Also one that I don't see mentioned: sometimes when I drag a unit over an enemy unit it doesn't show the combat odds, and I have to click away and then select my unit again before it will show the odds.
Since this is also mouseover behaviour I assume it's all part of the same bug, which appears to be a focus issue of some kind (does the game window have some sort of invisible child window that steals the focus from the main window sometime?).
Kinda reminds me of the infamous "yawning SAM infantry" bug from Warlords - seemingly random, and such a big problem (for those that haven't encountered it, there was a typo in one of the config files causing the SAM infantry's random yawning sound's min volume to be higher than the max volume. The game didn't know what to do when it encountered this, so whenever that sound got played it would freak out and play a hissing, shrieking noise at maximum volume. I and a few people I know were wearing headphones when we first encountered that bug...).
As others have mentioned, BtS's increased use of mouseovers in the form of Random Events has made this already-aggravating problem just that much worse.
It happens every couple of turns, on average.
To correct it, I click on my second screen and then back again, or alt-tab as others do.
p.s. hi, I'm new here.
