I think I know what I’ve done. I think I’ve laid out road splines with a mesh that has spanned multiple tiles eg x3_y1,x3_y2,x3_y3, but forgot to set current level for each one correspondingly, so all the road splines were owned by x3_y1, then when deleting them all, somehow a few roads have had their mesh remain, but the spline points be deleted, essentially orphaning some of the road mesh on a spline with no access points. That’s my theory anyway as it’s the only one that makes sense to me at the moment. I have no idea how to get rid, although I’m suspecting I might be better deleting the road mesh asset, then re-adding, to see what happens.