Help Please - Exporting to USB

I have recently bought a DDJ-RX and I love it, I use this plugged into my MacBookPro and all is fine. However, I find preparing my tracks a lot easier on my PC using another copy of Rekordbox as I have a proper keyboard and a mouse etc and bigger screen. I was under the impression I could then export my tracks and playlists to a USB stick and then pop that in my MBP and play the tracks I've just prepared. However, having spent 2 days organising my tracks and naming and gridding them all I can't get it to see the USB Key or import anything.

Is this actually possible? And if so how do I do it?

Please tell me I haven't wasted the last two days, is there anyway I can keep what I've done on the PC and move it to the MBP?