UE3 - UT3 Staticmesh LOD problems

Two problems I got when I was dealing with the staticmesh LOD in the editor.
1) In the staticmesh editor, choose menu "file-->generate LOD", choose LOD level, and click OK, nothing happens. Seems it's not working.

2) So I have to create a simplified mesh by myself and in the staticmesh editor, choose "file-->import mesh LOD" to import it as level 1. It's working now, but if I wanna delete the level 1 mesh in the editor or import a new version of the base mesh, the editor crashes!
WTH is that?

Someone knows how to avoid that crash? or it simply is a bug that we have to wait for EPIC to fix?

I checked the log file, it is the Generic protection error and no helpful message is there

Thanks!
Sure it's not necessary unless used in a very open level, but if it's working it is at least an option for optimization and I would like to give a try sometimes I think.