Rekordbox 4.2.5. Exporting stuck at 0%

Well, a fresh windows install on my laptop forced me to upgrade to rekordbox 4 which looks awesome when its finally running, having to create a bunch of new accounts again... But now i've started syncing, it seems to be stuck at 0% exporting or it's just terribly slow. Anyway where rekordbox 3 used to run an entire export and sync procedure in somewhere like 3 minutes, rekordbox 4 seems to take ages. The light on my USB stick is flashing but not constantly, it flashes for like 2 seconds and then stops for another 10. A quick solution is appreciated as I am about to perform in two hours...

Thanks in advance