I know you made this topic a while ago, but since no one has answered, and you haven't said that it is fix, I'll try to help. First you will probably need to reinstall Mable Story to get it working again, after it has installed, try playing it again, since a reinstall could also have fixed the issue that made your keyboard stop working.
If your keyboard stops working again, shutdown your computer, and plug in a wired keyboard. Then try to play it again, if the game stops working again just reinstall it again.
At this point the wired keyboard will probably still work where the wireless one stopped. If the wired one works, then either just play using that one, or if you really need a wireless one, pay a new one.
Tell me the results of trying these things. If the wired keyboard stops working as well, I would probably need to ask a few questions about your computer.