Be sure your league is setup properly before installing any scripts.Setup Video
The Custom Tabs scripts manipulates the MFL HomepageTabs so they can be placed on all pages , you can change the name of the "Main" tab , you can add custom tabs that are links and not actual tabs. You can also create multiple sets of tabs to display within your homepage layout. Here is a tab generator you can use to get started Tabs Generator. Tab groups created with the generator are placed in a separate homepage message and then added to different areas of your homepage layout. Each group must have a unique identifer , which is explained on the generator page.
The "script.js" file has an uncompressed version that can be edited and hosted on your own server.
All scripts require 1 instance of the cache.js file to be placed in a header message as the 1st line