Cursor not working

[jens]

This could happen if you click too much. For example if you double click on an icon on the desktop to start the game, but have the desktop icons configured to start on one click. Or if you start the Amnesia Launcher, and then after launching game click on the desktop or a window before the game is running can do this as well.

Maybe you can try to press alt-tab on the keyboard to switch to the desktop (after the game is running) and then alt-tab again until the game is the active program again. See if that helps.