There is only one file type that uses the .MMLP extension:
Music Macro Language Project
Project created and used by Macrotune, a Music Macro Language (MML) editor; saves all of the data and settings associated with a project, which includes the author, copyright, notes, and song title; can be exported as a .WAV file.
NOTE: Macrotune is a MML editor that specializes in the creation of "retro" style game or computer music.
Updated: April 15, 2015