Moving the topic? Done and done.
As for the level itself, the download has expired. Have you checked the map for errors? Most level editing utilities have a feature that will test your map for mishaps that could otherwise crash a map. If you're on Doom Builder, this is bound to the F4 key. Ignore what it says about texture errors, you should try to focus on any other errors that come up. Typically, things like overlapping linedefs can crash the game when they come into view. Also, this probably isn't the cause of the problem, but which nodebuilder are you using? Zennode, hopefully?