IGN has published my guide for Sims2 Castaway for Wii now, although it is a work in progress. Even though I have not been able to transfer all information from my game journals to the guide yet, it does have a fair amount of useful information in it.
One of the most vital 'secrets' of Sims2 Castaway is the potency of guarana, a spice that can be found in many locations on the islands. Using guarana in any cooked dish will give your Sim extra energy and allow him/her to pass through new Portals, exploring difficult terrain, whether on land or on sea.
Make certain as well that you create all possible tools as quickly as you can, as this will 'unlock' new items.
Accept deliveries from Chimps. This fulfils goals as well as allowing you to obtain a piece of the Treasure Map.
I have noticed something very troublesome where the PSP version of the game is concerned. It is extremely slow at the point of moving from one location on the map to another AND whenever you wish to save the game. I advise saving frequently, although it is a case of 'damned if you do and damned if you don't' as the game system has shut off more than once for some reason in the middle of saving, thus corrupting the data. My system never did this with any other game, so I only can assume it is a problem inherent in Sims2 Castaway. I therefore would caution players to keep more than one save file for their game. Furthermore, as the system shuts off randomly in the course of this game, usually when saving or using the map to move from one location to another, even when the battery is fully charged, one is in danger of losing valuable progress if one does not save frequently.
Apart from these problems, the game is fun. The Wii version IS superior, alas... I always would like to be able to declare that a game on a portable system is the equal of the same game on a console but in the case of Sims2 Castaway, the PSP version is not quite as good for the reasons I have given.
There are more clothing options in the Wii version as well... although that is a minor point of comparison