well crap. that response didn't post...
- try hitting ctrl-shift-alt all at the same time, a few times in a row - this assists in a lot of things, and potentially, yours, as I don't know what thing yours is.
- For example: Shift/caps being stuck and forcing you to type in all-caps, without having one of the keys pressed, nor knowing anything else is on. - even just turning on caps or pressing shift- just inverts the state, and doesn't shut it off (i.e, you'd type lower case except for symbols which would be alternate/uppercase)
- The other day I believe ctrl had managed to "lock" and was affecting me in browsers after quitting the game - CTRL-ALT-SHIFT helps in both cases. - It can stop a "stuck" key or toggle - afaik, that's its purpose but I could easily be wrong about that, and it just happens to work.
- Try hitting alt-tab, and holding it. - while holding it, try clicking in the game window - usually this just seems to "cancel" the alt tab, but I dunno, maybe its actually a form of selecting the window you want to choose with alt-tab. (honestly I don't expect this to fix anything)
- Try alt-tabbing while game is up, without clicking, immediately back into game. (again, not expecting this to fix anything,but either might help temporarily)
- Ensure there's no programs (like Task manager, but not Task manager specifically) that have priority or override to be on top of other windows all the time. - This includes Error messages from both MLBS and anything else - but again, not Task Manager. (TM usually behaves in this case.)
- An error window, especially from MLBS and especially if it was non-critical, can pop up and not take visual priority, but rest physical priority from something (i.e, You'd see the mouse suddenly have action, but you wouldn't see a cause)
- If, again, this was MLBS's doing, in some cases, minimizing the program with the error results in the error being hidden as well.
- If you feel like This could be the case - check drivers and the like, as well as the common issues for other runtimes/routines/etc that you may be missing or have out of date.
- An error window, especially from MLBS and especially if it was non-critical, can pop up and not take visual priority, but rest physical priority from something (i.e, You'd see the mouse suddenly have action, but you wouldn't see a cause)
- I'm not saying any of these are "right" just adding more possibilities to consider in case the "right" hasn't been found yet.