Not exactly the greatest way to compose an invite menu snippet, but as you stated it does demonstrate use of reading/writing text files which accomplishes your main goal. However this could be accomplished successfully without the text files as it seems it just circumvents the whole invite process. If you're looking to expand it and/or re-create it using some new identifiers, $input() and $findfile() may be of use. :)

The start event usually acts as both a load and a start event, in that the first time a code is loaded it triggers as well as every time you start mIRC.