This seems unusual. Have you tried to reinstall the game?
Viewing post in [BUG] Sandbox Crash
no i haven't. actually, i found that if the game succeeds in being created its playable. it just has a chance that the game will crash when first being created.
...but i realized i really dont like sandbox once i got in also. so i doubt i will do much more with sandbox regardless. it just gives you too much to start. there is nothing to work for really.