Copy the code that it creates. Open a new text document and paste the information in there. Go to File>Save As and save it as autoexec.cfg (make sure that you you specify it as "All Files" and not "Text Document" at the bottom of your save screen). Then browse to your cfg folder:

Code:
Program Files/Steam/SteamApps/youremailaddress/counter-stikes source/cstrike/cfg
and drop the new file there. It might be a good idea to rename your previous autoexec file (something like old_autoexec) before in case you ever want to revert back to what you had previously.