If the map is a public map, you may consider including the download here to see if others are experiencing the same issues as you are. It's possible that there was a problem with the map itself (missing/broken meshes, for example)--especially if it has been updated by the owner-- and it could be a matter of the map's doing as opposed to something on your part.
Try removing any particles that come with the map, as well. That shouldn't be causing the missing mesh problem but it could help with the crashing.