We are in the place with switches, and have, apparently, been spotted by the Harvester. We are, apparently in a state of battle with it. Not that it shows. We are in a room where we flipped a switch and got locked in. Clicking on it again does not open the way. Have tried this quite a few time. The switch itself keeps fading out and coming back. Have opened other switches without any problems like this. The atmosphere keeps turning red then back to normal. One of the dwarves keeps saying things like "it has become immune to magic attacks" (not that we have a mage with us) or "It is resisting our weapons" then says to change the way we attack. However, we are not attacking, and nothing appears to be attacking us. We are just stuck in the room and can't get out.
So, can anyone tell me: Have I hit a bug, done something wrong, or do I have to figure the way out?
Meh... tried to alter the thread header, and it still doesn't show 'spoiler' alert,

but at least it's in the page header...