[Ichabod Fletchman]

Try using the Keymap Editor addon, it makes this sort of thing really easy.

I said I do not want to map the favourites menu to a key but instead I want it to show up in the main menu. As far as I'm aware the Keymap Editor addon is useless for that.

Rather than editing the skin, you could take a look at the Estuary Mod
It allows extensive customisation to most areas of the skin.