Select the files or better the folder which containst the catz and gstz files of the Game System you want to see the rules of.
If you have BattleScribe installed, you will find them in your BattleScribe Data Folder. On a Mac the BattleScribe data Folder is in /Users/WhoEverYouAre/BattleScribe/data.
If you do not use BattleScribe or just want to have the files at a certain location, you can download the files in question from the BattleScribe Data Repository Select the Folder containing the files or select all the files manually and click upload to see the rules.
All rules will be listed and you can use your browsers search feature to find what you are looking for.
The Load button will be hidden. If you need it again reload the web page.

This app displays data that is provided by the Repository team. It's all their work, this app just makes it accesible.