If I was you, I wouldn't use that script. if you do not know what it does, do not use it! scripts can contain serious exploits, so it's very important to download scripts only from known and authorized websites (for instance: mircscripts
If you are being kicked by the administrators, then probably that channel was used for illegal activies, and maybe it has something to do with your script author - so, better watch out and use scripts carefully.
About your question, you can search the remotes for a 'join' command, or for the specific channel name.
To access the remote press Alt+R, then Alt+F to launch the find dialog. type the requested search string, make sure the "search all files" box is checked, and click 'find'. once you've found the requested command, simply delete it, or comment it out by prefixing it by the ; char.