Thanks Misu and Eileen, now I understand what is the meaning of having an Installation Pack, they come all together as a pack and works also together with the things inside, As mentioned by Eileen, a particular Style probably is attach or linked to specific voices, multipads etc etc. that makes use of them, that is the reason why they put it all in one piece or in a pack, probably some other styles do not need for voices or other that were manipulated or changed, they use the ones that are installed standard, so in that case that specific style could go in user memory. I suppose Yamaha is trying to make things a little bit easier for users, but in some cases this kind of things can be confusing when trying to understand the way they were done. Thanks for your support.