Gaming :: Mouse Stuck After Playing RCT1

I tried and have managed to run RCT1 almost flawless in compatibility mode (Windows 98/ME and run as administrator). The one thing that bothers me, is that after playing RCT, every window I click on becomes de-activated, except for the window you click on first (after the game closed). Whatever you click on outside that window doesn't do anything, even the taskbar. You can however navigate with no problem in that specific window.

Alt-tabbing to another window does work: it activates the window, but as soon as you click in that window, it becomes de-activated again. It sounds pretty odd, and I think it also is. It bothers me a lot because the only way it seems to go away is after logging back in. I've looked around in the taskmanager, but whatever I did there didn't solve anything. It also hasn't anything to do with the hardware, as both the external mouse and the touchpad (I'm on a laptop) have the exact same issue.