So basically topic says it all. I've spent for like 40 hours on my interior and suddenly when I tryed save it crashes. It crashes everytime when I try save my .esp file loaded.

I tryed load CK without my .esp and then I can save normally, so its my .esp file which causes the problem. I've only done layout and cluttering so far. So it cannot be lightning, navmesh etc which causes this.

Also memory usage is not big at all in interior.
Anyone have same experience? And anyone know how to fix this?

What do you mean by it crashes? When I save it can take up to ~30 seconds, during which time the ck will 'freeze' but once it's done it's fine. Are you sure it isn't just feigning death? It legitimately closes?

Does it give you some kind of an error when it does this?

I've seen it crash when doing particular things... don't remember exact what though. I know that it always crashes after trying to compile about a dozen Papyrus scripts; though I haven't messed with it since updating to v1.6 (the CK, and the assembler were updated).

Does it always crash when you try to save to that ONE esp or any plugin? Have you tried saving it after exiting certain dialogs (like the NPC editor, closing the navMesh toolbar, closing all open ref-editors, etc)?