Let's say you've created possibly the best console movie tie-in ever. Adapting its brilliance for PSP would be a doddle, right?
For a kick-off you'd do the best you could to adapt the two-stick first-person shooter controls to a nudge stick and four face buttons, co-opted to act like a D-pad. You'd do this, but privately acknowledge that the face buttons are spaced just too far apart for them to work as an intuitive setup during the often-twitchy combat.
You'd then edit an already short game (six-seven hours) down, isolating the lead, Jack Driscoll and removing any hint of the collaborative, film-crew-in-peril dynamic that fuelled the original game's tension - so it's just you, alone, fighting through Skull Island. You'd then introduce slow-down into the sections that have you controlling Kong and remove a number of show-stopping set-piece battles. Finally, you'd reproduce the beautiful graphics using brightness levels that combine with a low-contrast green/brown/grey colour palette to render much of the experience impossible to see in anything approaching natural light.