Just thought I'd upload this mapping for anyone in the same situation as me. I have a 4 Channel Mixer & 2 X1's. Now for love nor money could I find an "easy" way to have the following layout 
>mixer channel 1-2-3-4 corresponding to decks C-A-B-D in traktor with the first X1 controlling decks C-A (viewed from LtoR) & the second X1 controlling decks B-D.

I have an X1 positioned either side of the mixer and really wanted the above layout as I like to have A-B decks on the mixer channels 2&3. Don't ask me why it just seems more logical ?!!

I've tested the altered mapping and it "seems" ok but obviously it's better to get others opinions too. And in the sharing nature of DJTT (which btw is awesome) I thought I'd share this for anyone who does not like fiddling around in controller manager!

If your using a physical layout the same as mine then this mapping only needs to be applied to your Left Hand X1. The Right Hand X1 uses the standard layout assuming you have the options set right in the X1 settings. i.e.  "Two controllers - Controlled Decks - A+C / B+D".