Im having many issues with HLOD… system never really got off the ground for me… always been broken in 1 way or the other… it crashes unreal editor quite often when generating proxy meshes for certain areas. I noticed one reason for a crash in 1 area that fixed it was literally being forced to disable blueprint meshes from being included in it, but other areas are simply static meshes with nothing fancy in there… and it crashes the editor. I dont generate new textures… it should simply be a merge of meshes.