There are some changes/correction to my previous post.
6. All texturs must be vertical mirrored before they can be used in Celestia.
This point is not more correct since version 1.3.0pre3. Chris has now fixed this bug.
9. 3DS models can't cast and receive shadows that means the model is also lighted within the shadow of a planet or moon.
With a GF3 or better grafic card (hardware accelerated shadows) the model receive some shadows, not very perfect but it works.
I have now adapted my Columbia shuttle model and Doug Gann's lander model to the new Celestia versions. They can be downloaded from my Celestia page. I have also included new ssc files.
This is a shot form the Apollo 11 lander.