[The Goomba Mattress]

First of all, I appreciate the replies.

I currently am behind a router with an IP of 192.168.1.100; when I start a listen server through CS, it tells me the server IP is 192.168.1.100:27015.

If I'm understanding correctly, all I have to do is open up port 27015 in my router settings so that people over the internet can connect through that IP (192.168.1.100:27015). If that's the case, I already went ahead and forwarded port 27015 for the IP 192.168.1.100 in the router settings.

I've had experience with this before; one of my file sharing clients didn't work until I forwarded a port in the router settings and then specified that port in the client's options. If the same applies to CS and port 27015 is required to be open in order to receive incoming connections, then this should work.

Let me know whether or not I have any clue about what I'm talking about.
Thanks