When I tried to look through the telescope in Todelmer, the telescope will go completely grey at some point, and will not work.
I scouted the internet an found two people on the internet with the same problem and they gave up.
Not in any walkthrough is there a mention of this being part of the puzzle, is this a bug?

Also, the final gate to the final world will not open, despite the three slates being in place.
I would like to play the final part of the game please!