It worked!!! I started a new game without re-installing the game and I trashed the old game. I decided to play the entire game, rather than jump straight to Laki'ahn, since my co-playing friend will want to finish the game without having to go back through all the other ages.
This time the right-hand lever returned to its "up" position, as it's supposed to. The cage rotated, as normal, and I was able to go to the arena.
Thanks, Nanouk and everyone for all your help.

You had me worried for a while. I tought you would throw the game in the "trash can". Glad you made it. This Myst V game sure has it's own mind. At times, it seems it is at war with you.
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