Can I use RekordBox like this? (MacBook Pro, Toshiba netbook and two CDJ-2000's)

its going to be rough, maybe impossible to do that exact thing being that its cross platform and drive volumes are different, for instance, Mac does not use letters for drive and pc does, like your "C" drive, so it would be hard for RB to load the tracks being that they cannot differentiate the path

I would skip step 5, export from mac to external and then plug into cdj's directly.

I wanted to do your exact situation with a netbook and had no luck, create everything on my mac cause the screen is bigger and i use it for everyday use, then export the DB to my netbook to bring to gigs for the cdj's in case I needed to search for a track quick and load it, the smaller netbook at some places would be great due to constricted room, but oh well 

Is it possible to set the Mac to give the external disk a drive letter?

Or at least I guess it's possible to still import the database to the netbook (with a forced re-analyze), then connect the USB drive to the CDJ. That way you have all the tracks on the netbook with a rough BPM and artists/names, so it could still serve a purpose?

@Per Christian > It's going to be impossible in the first place because you cannot run Rekordbox over USB cables. ;) Both CDJ's must connect to the computer running Rekordbox via LAN cables. If you don't have 2 LAN connections on your computer, you should look into buying a simple Ethernet Switch with no administrative software on it.

Also, what BriChi mentioned is true about the cross platform compatibility. It will be extremely frustrating and difficult to switch your database from your Mac to your PC considering every time you add 1 new track to your Mac, you will want to export that track and all the hidden Pioneer folders, then add the new folders to your PC and have even more troubles with finding your library because it will be stored in a separate location on your PC than on your Mac. Don't get me wrong, it is possible, but it will take a lot of work every time you want to update your PC with new music, unless you just decide to add that music to your PC without the new Rekordbox files, and have the tracks analyze again on your PC and save their own files. Which in the end is basically pointless to even save it on your Mac then.

In my opinion, your best, easiest, and safest way to do things would be to have 1 main Rekordbox library that you always update and take with you to gigs. If you really need a library on both computers, then update each computer separately as it will probably save you a ton of time and confusion. :)

What is the purpose of having your Rekordbox collection on your Mac if you want to use your PC for gigs with a USB device?

It would actually be much simpler to just do steps 1-4, then connect your CDJ's together via ethernet, and plug your UDB device into the top of 1 of the CDJ's. Boom - no more netbook needed. :) One less thing you don't have to carry to a gig.

If you have more questions feel free to ask. :)