Hi!
Hey I have a sudden need to use my Launchpad (version 1) as a standard MIDI controller to 'perform' MIDI notes into an audio/midi sequencer - Afterward I will play the audio track to my speakers, and the MIDI track back into a computer (from external interface - Tascam US-1641) to trigger light scenes (using American DJ MYDmx program).
The MYDmx program can accept note/on note/off MIDI data to control the scenes I set up.
However, it will not accept the USB hosted input from the Launchpad.
So.... I need to convert the Launchpad to a 5-pin DIN (MIDI note/on note/off) controller.
~I don't care about lights in the Launchpad~
I could do this with any MIDI keyboard I have laying around.
However, the Launchpad provides a nicer layout for assigning light scene changes! 
It looks like you were able to accomplish this functionality?
I'd be interested in chatting with you to see if this is something I could build and program
easily to use my Launchpad for the whole reason I bought it LOL.....
THANKS!
Jeff