I'm not quite totally sure what ur asking but how to add a server by IP in 1.6 is as follows:
1. Get into CS 1.6
2. Click Find Servers
3. Click Favorites
4. Press Add Server
5. Paste or Type Ip WITHOUT spaces anywhere (Note: if you type a space before, between or after the IP it will display <Server Not-Responding> Error)
6. Press Okay
7. It should come up, If it displays <Server Not Responding> Either the server is down, You typed the IP wrong, or theres something blocking it from getting out.
If all doesen't work a good idea is to goto the www.steampowered.com forums (a tab at the top)
They are the Valve forums and you would get more directed help there.