This is the lava level, the mine beneath the monastery, a series of cave tunnels (not the MYSFAC factory). Here and there, you find control panels to operate heavy equipment like generators. When I click on one of these panels, a screen overlay pops up, showing diagrams, text, and a flashing red light in the bottom left. Problem is, at this point the mouse buttons and keyboard become totally unresponsive. I've clicked all over the panel controls but nothing happens, and I can't get out of the pop-up by clicking outside it, or pressing F3 to reload, or anything. I'm forced to ALT+TAB and shut down the game in Windows.

Anyone know how to fix this?

I came up with a workaround.

Mysterium Levant is broken into 3 areas to load: "Levant Entrance", "Lower Levant", and finally "Lavatic Pump Area".

What I did was basically to skip Levant Entrance by using the "noclip" cheat to get past the big gate near the top of the level.

1) Press ALT+Shift+F10
2) Press the tilde key (the one with ~ and `) to bring up the cheat menu
3) Type noclip and press Enter
4) Press ` again to close the menu

I passed through the door easily, turned off the cheat, and entered Lower Levant.

Lower Levant still had some buggy console panels that forced me to ALT+TAB out of the game. A couple others were not buggy (or stopped being buggy after I solved storyline puzzles) so I actually finished Lower Levant without the cheat. Lavatic Pump Area didn't have consoles.

All that in an hour? I admire your speed. :) Haven't encountered that bug, but your workaround should be of use to someone else.