https://gist.github.com/MCEventHorizon/22733dc6d4e5027f99a1ee839eb5d7f2

Going to need to know which vehicle you placed at the time of this crash, from which pack, and which version of the pack you used.

Impossible. The crash report you sent indicates that there's a vehicle that had a bad JSON that was being rendered at the time of the crash: java.lang.NullPointerException: ERROR: Rotatable part definition:$Gearshift is missing a rotationAxis in the vehicle JSON!

Didn't place any vehicles, it was a newly generated world, after the world was reset, I couldn't replicate the crash.

Since I can't replicate it now even when placing vehicles, should I close it for now?

Er, I'd say so. If I can't know which vehicle has the issue, then it'll be impossible for me to test or tell the pack authors to fix.