I didn't actually think of that, what a wonderful idea. It should be possible, given that it should be easier to get the necessary objects from the level editor and be able to place down those objects as if they were created by the player - maybe. Although it might be a while after the...
Hmm thats interesting, I was though you were using a lower resolution and that was causing the problem. Could you please take a screen shot of the issue, and also check to see if besiege is running at your resolution.
Making your own blocks is not rocket science, if you are willing to learn some skills then anyone can create a modded block. Spaar and TGYD have made it very easy to create modded blocks! TGYD has made a tutorial (written) for people who want to create their own blocks, which takes you through...
The mountains also don't seem to count as being real, as using fuctions while building like move machine to ground, places the machine on ground level :\
Well that was not supposedto happen XD. I guess the game is simulating while in the main menu, which a problem. Just call it a 'feature' for now ;).
As for being unable to load the sandbox, I believe is caused by either because the machine is already loaded and the game trying to load already...