ok there are 2 reasons first of all 1.does the mod load and then gives an error after bout 5mins of play 2.or as soon as map loads if your prob is number 1 then may i ask do you have a menu in your mod if yes you can avoid it by not overusing it btw other ppl can crash the mod too
if you have a menu try that if not then i cant help
BTW i used a menu in my wolfenstein mod and it did the same thing prob with menus is it loads too many scripts so game runs out of space take this for example there is an empty box (mod with no menu)
and you start to fill it with thrash (mod with menu) and when its full you know what happens next XD hope i helped