Decided it's not 'cheating' to look up how to solve a puzzle i've already solved myself at least once -- so got uru book i bought a while back and found sequence to activate power in gahreesen. from there, went up elevator, and jumped across to other building on first try. (no problem running uru on laptop -- though the myst v 'trailer' did not run well on it, a couple years ago; the sound kept dropping out.) found stonecloth -- it links to yet another city balcony, which had a power marker. (so those collecting all the power markers really do have to replay substantial portions of the game to get them.)
There's actually nothing else to 'do' in Gahreesen, until accessing the prison cell via the link at the end of Teledahn.
In mentally reviewing, the two areas of most difficulty in all of Uru, in terms of manual dexterity, are the jumps in Gahreesen, especially at the end down onto the rock pillar, and kicking the wooden buckets around in Eder to make a bridge you can carry the fireflies across. And in the expansion pack, having to swim to the small island in Adonay, which perhaps isn't always necessary. Aside from those, replaying the entire game with a puzzle guide at hand shouldn't actually take very long -- two or three hours?