Final solution: MPD24 w/ Traktor (revised)

You'll need the latest version of Traktor to get the most out of this.
Just to start this off, I won't be posting my .TSI file for this. I believe that setting everything up yourself will allow you to modify my settings to fit your own workflow. Plus it gets the creative juices flowing and will let you come up with ideas I can steal from you later.

The easiest way to look at it is to believe of each of the vertical sets of 4 pads as functions corresponding functions to each of the 4 decks in traktor. Like a channel strip on a mixer.

In the end you will be able to control all four decks with ease, mash fx like mad, do your entire set without touching your mouse and generally have a blast with traktor using only one midi interface laid out in a logical manner.

Firstly, I have some main functions mapped to my laptop keyboard that are also mapped to bank A of the MPD. That way they are still accessible when I am fooling around in other banks. These are as follows:

Load into decks
A=deck a
S=deck b
Z=deck c
X=deck d

These are for scrolling thru cue points and other various stuff:
K=deck a backward
L=deck a forward
;=deck b backward
'=deck b forward
o=deck a decrease loop length
p=deck a increase loop length
[=deck b decrease loop length
]=deck b increase loop length
9=deck a pitch down (set to default)
0=deck a pitch up
-=deck b pitch down
==deck b pitch up

The following keys set the automatic loop point of the corresponding decks
Q=deck a
W=deck b
E=deck c
R=deck d

These row of keys above simply toggle "loop active"
1=deck a
2=deck b
3=deck c
4=deck d

These keys are set to turn on cue monitoring when held down. I find "hold" makes things less confusing than "toggle" since you don't have to worry about them being switched on by accident if they are not held down.
F1=deck a
F2=deck b
F3=deck c
F4=deck d

This set of keys are for simply triggering play (I also have C and B on the qwerty assigned to cup play on release. Works good for lining up tracks like letting go of vinyl)
F5=deck a
F6=deck b
F7=deck c
F8=deck d

The keys below those bend the tempo of those decks
5=deck a tempo bend -
T=deck a tempo bend +

6=deck b tempo bend -
Y=deck b tempo bend +

7=deck c tempo bend -
U=deck c tempo bend +

8=deck d tempo bend -
I=deck d tempo bend +

These keys simply reset the loop length value to 32 from whatever it was at before (which is handy if you notice right before triggering a song that it's loop length is set to 1/8 from the track previous track you had going on that deck)

F9=deck a reset loop length to 32
F10=deck b reset loop length to 32
F11=deck c reset loop length to 32
F12=deck d reset loop length to 32


AND NOW, ONTO THE ACTUAL UNIT!...
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Let's save the pads for last. I will simply name the faders and knobs by their names on the unit to make their functions easier to map for you. Most of them simply replace the need for a mixer

Faders:
F1=Pitch knob for focused deck (deck focus scroll is assigned to spacebar)
F2=deck a volume
F3=deck b volume
F4=deck c volume
F5=deck d volume
F6= controls all parameters for all the chained fx inside traktor simultaneously. (more thoroughly explained in bank B layout)

Knobs: (These are all set to eq deck a/b. I've also made a modifier so when I hold down a key all these knobs adjust the eq for decks c/d instead of a/b)
I prefer having my eq knobs only go to 0db max. Since the mpd24 has endless rotary knobs, I don't like to have to look at my screen to know when it's reached 0db. Hence why i've setup the mpd to only go to max value of 62. Plus as a DJ I simply prefer to take away eq instead of adding it. You can set it up however you like.

K1=deck a low eq (set to max value of 62 on MPD) (raises to unity gain)
K2=deck b low eq (set to max value of 62 on MPD)
K3=deck a midlow eq (set to max value of 62 on MPD)
K4=deck b midlow eq (set to max value of 62 on MPD)

K5=deck a mid eq (set to max value of 62 on MPD)
K6=deck b mid eq (set to max value of 62 on MPD)
K7=deck a high eq (set to max value of 62 on MPD)
K8=deck b high eq (set to max value of 62 on MPD)

Bank A pads:

X X X X Loop active on/off
X X X X Tempo bend +
X X X X Tempo bend -
X X X X Play
A B C D

Bank B pads:
Requires a bit of explanation. The latest version of Traktor allows 4 fx units to be used at once. If you use all your fx in chained mode instead of advanced, you get 3 fx per unit. 12 fx and all. I use all 12 fx at the same time. Choose whichever fx you want and put em on whichever of the 12 pads you want.

The bottom row of pads on my MPD are set up like this

pad1=toggles on/off for all 4 fx units on deck a
pad2=toggles on/off for all 4 fx units on deck b
pad3=toggles on/off for all 4 fx units on deck c
pad4=toggles on/off for all 4 fx units on deck d

The remaining 12 pads turn on each of the 12 fx in use when held down. Additionally due to the bottom row of pads, you can for example, have 2 tracks going, with all fx units on for deck a & off for deck b, strike pad 1 and pad 2 quickly on the mpd, and the fx will instead alter the sound of the opposite decks.

Be creative. Hold down the pad you assigned to the delay, then hold down the beatmasher, then the transpose and if shit gets too crazy, just let all the pads go, throw the switch down and the song is back to normal.This shit RIPS and looks like this in execution...
http://www.youtube.com/watch?v=eeA6rVj473o


Bank C
This bank is for doing a rewind on tracks. as well as hammering out drum beats using cue points in all 4 decks. I have them set to utilize hotcues 1-3. The best part is that the rewind button literally works just like the real thing. the faster you hit the button the faster it rewinds, and when you hold the button down it functions like holding your finger down on a record. You can use the top 12 buttons for either choosing where you want the track to start after the rewind, or beat juggle cue points if you've set them up in clever fashion. Here's a video showing how it works. The mapping is also in the youtube description.
http://www.youtube.com/watch?v=5PbZQmecJKk
X X X X Cue point 3
X X X X Cue point 2
X X X X Cue point 1
X X X X REEWIND
A B C D

Bank D is pretty straight forward. Top row of buttons increase the loop length value of each deck and so forth. Bottom two rows allow you to beatjump seamlessly through a track (as opposed to the rewind)
Bank D
X X X X loop length +
X X X X loop length -
X X X X beatjump +
X X X X beatjump -
A B C D


Hope this helps some of you struggling to make this controller useful for a program like traktor. If you end up using this and you spot me in a bar, buy me a long island!