I've had this bit of glitchiness in a few areas, but it was generally a small area.

Unfortunately here it not - as I approach the bridge with the Beholder control panel, suddenly I can't see, similar to a Darkness spell, but Ultravision has no effect.

Unfortunately you kinda need to be able to see to pass this puzzle. I've tried a few quick resolution changes et al to no effect ... has anyone else come across this?

Is it a full black screen or does it just get darker (as in if you turned the brightness all the way down) ?