Ever since 4.14, I’ve been unable to properly reimport modified speedtree assets. I’m not sure if I have discovered any specific repro steps, but I know that my only workaround is to delete the tree and its assets and import it again (force deleting everywhere it’s been applied)
I’m under the impression a newly imported tree will reimport fine until I shut down UE4. If it start it again and reimport the modified tree it seems to be crashing.