Splinemesh does not generate navmesh


I’ve made a blueprint for generating splinemeshes. Almost everything in the image below is a splinemesh of some sort. They all have player collision, “Can effect nav mesh” turned on, etc. Some generate some navmesh, like the stairs, but large swaths of the level are ignored and do not generate nav mesh. I’ve tried about everything I can think of, but still no luck - I’ve tried about every setting on the NavVolume itself, on the splinemeshes themselves, on the mesh the splinemeshes use, etc. Curious if anyone has any final suggestions?