Editing skeletal mesh LOD crashing unreal

Hi there, I have a set of skeletal meshes with some LODs each one.

Since I made some changes in the meshes and updated then in UE4, everything started to go crazy:

  • when importing LOD0, new lods where automatically created (I had 4 lod and now I have 10)
  • when trying to remove one of this lods, Unreal crashes with no useful description given
  • this started happening in UE4.16