So, as the title says, I can not change the Z level when in look mode. I have tried changing the hotkeys, but none of it works.
Do you have 3D FOV on?
You didn’t specify a version, so I just guessed.
Tested this in build version 10766 and it works fine.
As @anothersimulacrum says, you have to set the Options->Debug->Experimental 3D field of vision to true to be able to look around other Z layers.
(And Options->Current World->Z-levels have to be set to true as well, as it’s per default).
gah, that fixed it. thanks guys.