Now the first step of this fix works, the wormhole is gone
But the new skydome needs now a different texture mapping because with the default mapping, the movement of the clouds looks not so good.
I made a tiny video of the current state, it need DivX 6.0
http://rapidshare.de/files/6411131/clouds1.zip.html
http://www.divx.com/
My next step is to experiment with different uvw maps and sky/cloud textures.