Some work by following a specific method. The method is mentioned in my comment under this post: https://forum.plutonium.pw/topic/22301/how-to-play-custom-zombies-maps-right-now/17
Some others will crash even if you follow the method mentioned in my comment. I tried to investigate why it happens on the Kowloon custom zombies map, and I came to the conclusion that it’s caused by the custom map having too many weapons as well as conflicting ones.
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