(adsbygoogle = window.adsbygoogle || []).push({}); I have been thinking about using new games using my cfw slim, and i have had an idea would it be possible to install a newer game via the XMB (PSN Game Style) and then update to newest firmware to be able to play the game, this is of course only untill your done and then downgrade again??

no because XMB pkg is revoked in 3.70.