Most functions in Ableton Live can be easily mapped using the built in MIDI learn functionality. However, features that are buried in a menu or do not have a button in the UI cannot be.
ClyphX is a MIDI remote script that allows a user to custom map some of these functions to buttons on a MIDI controller, record and send SysEx to external hardware, execute several actions with X-Triggers, and more!
The video below delves into custom mapping some functions to an MPD32.
The latest version of ClyphX can be downloaded here: http://beatwise.proboards.com/board/5