Crash when applying new sub-material after reimporting SM

I’m experiencing consistent crashes when applying a material in the SM-editor IF the SM has been re-imported AND the SM had been assigned an additional sub-material in the modelling program.

For instance:

  1. I modeled a simple door with one material → imported in UE (without materials) and inserted in level.Applied one material in SM-edit mode.

  2. In the modelling program, I add a door frame with another material → re-import the fbx (door and frame in same file). If I edit the SM and try to apply a new material to the empty slot - UE freezes and crashes.

Workaround for now is: delete the SM from the level and content browser, import as new etc.

Several crash reports submitted. Last one is:

M-id: EF8496BB429129B284A64F9D71A1E69E

E-id: 318bd546ef6e466b939f63f35437e69c

Hi maxbrown -

Thank you for your report. We were able to reproduce the issue internally and have entered a bug report, UE-15663 for reference. We will keep you informed as we investigate a solution.

Eric Ketchum