Runtime error + server crashes

Salmon was having the same problem, remove some un-used addons (weapons, certain bricks that you aren't using, etc)and the game should start up smoothly.

If you still can't get the map to load try loading it up on a different server (mine for example) and if it still happens there it's something wrong with the save and therefor you would have to restart, but if it starts up on any other server its something wrong with your game or something else

do this