Welcome to mIRC tech support. You might not know it, but mIRC is a text chatting software client for IRC. We don't advocate using mIRC as a 'file trading' client, nor do we encourage or teach how to obtain illegally obtained copywrited items.
If the admin at the college says you cannot open additional ports, then you are bound to follow their rules. Many colleges are now actively going after their students who trade/receive illegal files though their servers. Really assess the risks you take with this activity.