DJR400 XLR Booth Output -----> XLR Nano Patch Input
Nano Out, TRS Jacks, ------> XLR Rockit
Take your Nano to Maplins, and grab yourself some of the below and an assortment of different adaptors(Gig savers for the DJ), the staff there are usually knowelable and will help you out.
The above cable would work from the Nano Output, 2 x of these from the Nano to your rockit
If you have XLR Cables already and you need adapters these kind should work