Ofc you need to change the url to your own steamtotp.cgi script, and also change the steamtotp.cgi script to output information in format USERNAME:PASSWORD:TOTP cgi script (as mentioned in previous post here) returns the username, password and auth code, thus you could make sure your primary computer is not compromised before allowing login to proceed. You can easily add authorization checks before your.
Also made this nice VB.NET app for login on trusted computers.