Please help! I'm stuck on this same puzzle. I've got the runes/tablets, guessing they have something to do with it, but I really don't comprehend what I'm meant to be doing...
This one makes more sense once you understand it. First of all, you need a total of six of these stones. If you don't have six, head back through the areas you've already visited (including earlier floors) and explore until you find them all. Remember that you can break gravestones with a pickaxe (at least one of these stones is in a grave, if I recall correctly). Anyway, the puzzle has two stages.
For the first stage, you need to rotate the dials repeatedly until the symbols on the inside (not
the outside) match the strange symbols shown on the floor in the chambers you explored earlier on the same floor. Once you do it correctly the ghost will congratulate you in a short cutscene and some small pedestals will rise from the floor.
The second stage is much less straightforward. I never managed to work this one out logically, but there is probably a way. Anyway, check out the walkthrough on GameFAQs
for the specifics (it has a fixed-space diagram so it wouldn't paste in here very well). Note that his instructions say to combine the stones with the platforms, but this is incorrect; you must place the stones on them by dragging and dropping (attempting to combine them won't work).
Once the second stage is complete the ghost will congratulate you again and the path will open. Hooray! :)