I started making my first map today, and after a couple of hours, I wasn't able to run my map anymore. What is happening is I'll press F9, the Run Map options box will come up, then I'll click okay, then the box that goes through the compiling progress comes up, but once it's done it'll close and Portal 2 won't open. My computer doesn't freeze, and I don't even get an error. Hammer will continue without a problem. I tried making a skybox and the same thing still happens.

Any advice as to how I could fix this would be great,
Thanks

Edit:
Okay, so the problem has arised again after I had solved it once (though I guess that means I actually didn't solve it? Whatever, ha) After reading the compiling log, and looking up some more information on leaks I'm still not able to find the leak on my map. I've inspected every edge on my map throroughly, many times over. I found where the apparent leak is after loading the pointfile, though it doesn't actually lead me to a leak. The red line just leads right into a closed surface, I've looked around each end of the line. I also do have a spawn point and a light in my map for the record.

Excuse my noobyness, and again, any help is appreciated.
Thanks