Runtime Error?

I was compiling my map and went away from my PC to do things because I knew it would take a while, so when I come back I see the last thing on the compiler is " Buidling Facelights… " and it finished them, then after that I saw no error messages, except in a seperate window there was this;

What does this meen and should I do something about it?

Well, do what it says on the little window: Contact the programs support team, aka Steam :v:
Other than that I have no idea, you should just send a support ticket to them though perhaps.

Alright I guess I will, I’m currently compiling it again to see if it will work this time, and if it does the same thing I’ll see about contacting them.

It takes you 12 mins to do your lighting? Unless the map is massive you should lower the lightmap scale on some faces.

12 minutes is fine for lighting. I have no idea why this error occurs, have you tried compiling through hammer rather than a batch file?

Probably a dumb question, but what do you mean?

And I think I already am compiling through hammer.

Also my map is fairly large so far, incase you were wondering why it takes 12 minutes to load the lighting.

Try resetting game configs. Looks like hammer is launching vrad wrongly.