Fortnite client crashes on round end and during Memory Calculation on physics islands

Summary

On islands that use physics , the Fortnite client reliably crashes in two situations: (1) when the round ends during a UEFN play session, and (2) when running a Memory Calculation from UEFN. Because Memory Calculation is required before publishing, this makes it impossible to publish updates to the affected map, and the round-end crash makes normal playtesting/iteration extremely slow — every test run ends with a client crash and a full client restart.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Stability

Steps to Reproduce

  1. Open a UEFN project and turn on physics in island settings
  2. Launch Session and join with the Fortnite client.
  3. Start the game, let it play out for a moment, and end the game. (99% of the time it will crash the Fortnite Client
  4. Alternatively, from UEFN run a Memory Calculation on the same project.
  5. Observe: the Fortnite client crashes during the memory calculation.

Expected Result

The round should end normally and Memory Calculation should complete.

Observed Result

The Fortnite client crashes to desktop both when the round ends during a play session and when a Memory Calculation is run from UEFN in a Physaics island.

Platform(s)

All?

Additional Notes

The only good news is this appears not to affect live versions

Doesn’t seem to be 100% repeatable on my island. Ending the game does crash sometimes, however, I was able to perform a memory calc and publish a new version (Private code: 8442-8235-6292)