Fog/vehical problem

[Steel]

um ive been working on a map for like 13 hours now and i finished the whole thing except fog i tested my vehicals they worked i could get in them and drive around in them shoot them everything worked fine i put in fog from backwash and it worked when i went to get into a vehical the game froze i tried to redo it but i got some thing that said like ident object/vehical/warthog it came up 10 times about and then same with scorpion and ghost i no its not the vehicals cause they worked fine before i added fog and i didnt edit them btween testing them and putting in the fog maybe someone could help heh i dont really want to loose 13 hours of work