I have almost completely reverse engineered Cartooners' (year 1988/1989, developer: IDTA, publisher: Electronic Arts, MS-DOS version) actor file (*.act) format and made a program that imports and exports actor templates. See: Cartooners actor file
Right now I have also made a start at analysing Cartooners' music (*.mus) files. What I already know about the *.mus file format can be found at: Electronic Arts MUS. I've little experience with wiki's and had to reformat the contents of a plain text file to put on this site. I might clean it up later on.