Hi I've finished all puzzle game of easy normal and difficult levels and the impossible is locked ... I don't know how to unlock it :(
same problem with time attack and some of campaign ('secret missions')
someone know how to unlock it ?

Just go in the Shop! You really are strange for not seeing the shop.

I 've bougth all puzzle all campaign and all time attack exept 10 and it's locked too!! ... I can play it but there is a cadenat and so can't win medals

Well, there's only 1 thing too do. Wait for a FAQ too come up on the internet. It'll most likely come up at www.gamefaqs.com 1st.