Ok, I am working now on two things - resized planets and mining facilities. However, if I try to import a brand new sphere model for my planets, I get weird results, the entire planet is a pulsing blue shade. Tried pretty much everything, but if anyone has succeeded in planting a resized planet ingame, let me know how you did it.
The best thing is, I managed to do it once, but have forgotten since what it was I did. 
The other thing is, I need the vanilla asteroid mesh for size reference. More than that, as my mining "facility" is actually gripping the asteroid with huge limbs, so I need to pose them correctly, and I'd hate to do it via trial-and-error method. Unfortunately, the only way I know to export sins meshes into a readable format in XSI is via the unofficial plugin for 3DMax, which I haven't got... so if anyone's got five minutes spare, could you please send me the mesh in .obj format to mansh00ter@yahoo.com, I'd be much obliged.