@tib_hou Very sorry for the confusion, ‘Minimun num converted instances’ option was added recently, the default value of “2” might puzzle other users if they’re following the manual. I’ll change that in next update.
@Macw0lf I’m currently investigating the lightmap issue of HISM, it seems an editor issue when applying lightmap data (it’s correct in PIE). I haven’t nailed down the problematic code, will update you if I’ve more finding.
The workaround of the issue is after the lightmap been built, save and re-open the map, you should notice the lightmap data apply correctly.