The "env" folder has the environment pics, or the 'sky', in it. In order for it to work it needs "lf", "bk", "rt", "up", and "dn" attached to the end of the file names (but before the extention). It would look like "myskyrt.jpg", "myskyup.jpg" etc. It looks like to put in the world spawn an empty "sky" key, so it is looking for 6 non-existant files. However, I that shouldn't make the game crash.
Ok, I took a look at your map file, you don't have a worldspawn for some reason. It should look something like the first pic. Yours is the second pic.