To clarify, you’re experiencing a crash when you save your level after adding a cartographic polygon?
Could you try to replicate the issue in a new project, with just Cesium World Terrain and the cartographic polygon in the level? That will help us figure out if it’s something up with your level/project or the plugin itself.
Cesium for Unreal is not currently compatible with World Partition, however it shouldn’t be crashing, so we will look into this.
You mentioned you have already tested on multiple machines, and in multiple different projects. One more option you might try is reinstalling Unreal Engine completely. I’d be surprised if it worked, considering you tested on multiple machines, but it’s worth a try.
To help us get to the bottom of this issue, can you provide additional information about your setup? Specifically:
System information for the impacted machines
Version of Unreal Engine 5 that you are using
Any additional plugins or code modifications that you may be using
You can provide this information to me here or post it directly on the issue.