Q:
Where is the eighth signal tower, the one I cannot find on the map?
A:
Its located directly in the northern apsis, at signal station B.
Q:
I still can't find all eight towers? Where are they?
A:
Look at your map.
The lowermost mark on the northern map has a "2x" to it;
maybe you are missing one of those two.
Q:
I found one set of blueprints that tell me that I need other blueprints for
some "regulating round" device. Where do I find those blueprints?
A:
With the first blueprint, you certainly found a little key.
This opens boxes in the same room which contain blueprints for several devices.
Q:
Is there any "time limit" per se that one must complete this mission in?
Depending on Karras messages over loudspeaker, maybe?
A:
This mission has no time limit, fortunately.
Q:
How do you open the door to the Signal Room?
A:
You don't. You get there from the other side,
after you've solved the jumping puzzle in the northern apsis.
A vine arrow may come in useful at the end of the jumping puzzle.
Q:
I cannot find that jumping puzzle.
A:
Find the round room with a fountain between bay D and bay E,
go to the northern apsis from there,
you arrive on the second floor,
and the jumping puzzle will become obvious.
Q:
Any way to get at Karras in his bunker? I tried many things, but none worked.
A:
No.
