Between 2012-2013, I was an active member of the Super Mario Galaxy 2.5 project. The goal of this project was to bring new galaxies to Super Mario Galaxy 2 for the Nintendo Wii. The project was ultimately cancelled.
I wrote two graphical interfaces for programs made by blank.
astConverter allows you to convert mp3 and wav files to ast, the music format used in Super Mario Galaxy 2. It also converts the ast files back to every common format. If a converted file sounds too quiet in the game, there is a gain feature built in which can amplify the volume.
Nuntius Novus (msbtEditor)
Nuntius Novus is an msbt editor for Super Mario Galaxy 2. It allows for editing the dialog in the game. Nuntius Novus supports Japanese character sets and can be used to add new dialog entries. It also works with custom msbt files.
png2bti is a command line wrapper which converts a png file to bti (image file used in Super Mario Galaxy 2) and vice versa. It relies on nconvert and tga2bti by LunaBoy.