Need help with DrSchottky multilauncher

I don't know if i can ask for it but i would like to modify the index.html in the multilauncher https://github.com/DrSchottky/3DS-MultiLauncher
to change the regionthree button with a cakes one launching cakes.dat instead of regionthree.

I have tried to modify index.html with wordpad and firefox but i understand nothing to the source code