traditional yurt corkscrewing prevention

[froit]

To add to Yves (mostly sound) advice:
the four ropes that go from the crown to the wall in each cardinal direction DO NOT HAVE TO GO THAT WAY. They are called 'ropes to fix small problems' in Mongolian, and that is what they are for. A twisted crown is a small problem. Falling rafters is a small problem (unless they fall all of them).
Undo one or two of these ropes, and work them over the rafters clockwise or counterclockwise, whatever way but contrary to the direction the crown seems to be twisted in. Then pull them tight as hell. Since your yurt is felt-covered, it will take quite some long-slow pulling, because of the friction. But it will work.
Twisted crown-syndrome is very common also in Mongolia.