if you look in the about tab in preferences ,, it might be stored there .. on the later versions it was placed there ,, not sure about the version of Cross DJ le that was supplied with the ion DJ bundel ..
no serial number is keep by mixvibes its up to the user to put it in their profile ,, where they can retrieve it any time ,,
all that being said,, Cross DJ ..up to version 3.43 will work with this controler,,should have the MIDI map for it in the software,, not sure that version 4 has the mapping ,,it should ,,think its termed Cross DJ ver 4 .. the pro version has time code support ,,which you might not need
hope this helps ..
