Ok so I was making some aerial faith plates and Hammer crashed. Well, its happened a few times to me so I just reloaded my map. Usually I can reload my map, this time it reloaded an autosave. So I exited out, reloaded the last backed up copy of my vmf I had, and started over again.

Now when I go to compile, it says it cant find the prt file. How would I go about recreating that? Ive spent do much time on this map, and I am really freaking out here.

Edit: Sorry, it actually says it cant read the prt file, not that its missing.

Although it is missing from the sdk content maps folder.

I believe you have a leak. Is there a leak error at the start of the compile log?

Post your compile log. You don't really need to, you definitely have a leak.