I'm very sorry for taking so long to look at this.

In your first screenshot you don't seem to have added the "TY_ModLoader.js" file to the "index.html" contents.

At the top of the "TY_ModLoader.js" file the first tutorial step mentions adding a specific line to the contents of the"index.html" file.

But if you did do that and it still doesn't work let me know and i'll try responding faster this time around.