I thought I did it right, but there was a small mistake somewhere in my cave addition and when I tried to fix that I just made it worse. I didn't realize this until after I saved. Now I have a few small gaps because a couple of cave pieces aren't exactly where they're supposed to be.
The problem is that...
1. I'm horrible at level designing.
2. My middle mouse button is broken, making navigation awkward.
3. I can't really undo it easily by having the CS ignore all my faulty changes to the cave, because part of it are intended changes.
I would be very grateful if someone could have a look at my esp and fix the issue, it shouldn't be very difficult but it would help me a lot. If someone has a moment I'll upload the esp.
And I'll mention you in the credits section of the mod?