@Kandeichan you just have to register your product at cryptons official website after creating an account there Theyll give you a link from which you can install the voicebanks onto your DAW Then you would have to use the vocaloid activation tool ( i cant remember where it's from) and input the code That will make the voicebanks permanently in your DAW Or else 2 weeks after your download, tge voicebanks would be gone and you woulf have to redownload them
I'm not familiar with V3 and V4 activation procedures... Are the serial numbers "new?" Can they be activated on the buyer's system, legally used, registered with Crypton for commercial songmaking, etc.? Thanks!