It should be pointed out that the flood protection mIRC implements is to protect your outgoing messages, not incoming ones. This means mIRC will queue your ctcp replies, message replies, etc. - It will not ignore people for sending messages unless they are CTCP requests that mIRC replies to.
If you're simply trying to stop people from flooding a channel with text, you'll need a script for that. Realize that you can't get flooded off a server unless you have a script that replies to messages- simply reading server data will not cause excess flood.
