This guide will show you what folders you need to backup should you need to backup some files regularly, or you are simply transferring saves. It also explains what the files in the folders do.
Package Files and Caches
Many issues and glitches can be solved by deleting or transfering .package files within your Spore folder. Note, some of those are critical and will mess up your game if deleted or renamed. They can be found in following directories:
Mac: Username > Library > Preferences > SPORE Preferences > p_drive > User > Application Data > SPORE
EditorSaves.package is the index of all that's in your My Creations and Everything of Sporepedia
*CRITICAL - do not delete when refreshing regen or the game will screw up.
GraphicsCache.package is the cache of 3D models of all creations
*non-critical - the game will easily regenerate all the 3D models from the png's
Planets.package contains a png of every planet you visited
*CRITICAL - needed for your saved games to have proper creatures.
Pollination.package contains all creature, vehicle, and building cards (png) in your Sporepedia
*non-critical - delete this if you wish to refresh your in-game Sporepedia.
\Games\ contains your game save file (Game0.old is backup)
*CRITICAL - deleting this will ruin all your saved games.
\Preferences\ contains your game settings.
*non-critical - deleting this may resolve settings-related issues
\MVJCache\ contains image cache of ingame sporepedia
*non-critical - no reason to delete these files
If you find yourself with a double of one of the non-critical .package files you can safely delete either one or both. If the problem stil insists or a double was created again, delete both files. Alternatively, you can add the suffix .old to make a back-up (or simply drag it into another folder).
These files should be transferable between the PC and Mac version and are important to back-up if you need to re-install your game without losing your save games.
Backing up Creations
When you create something, a png will be stored in the My Spore Creations folder. You can find that in your document folder in following directories:
PC: Users > Yourname > My Documents > My Spore Creations
Mac: Users > Username > Documents > My Spore Creations
Re-pollinating the game won't re-download them. Therefore it is recommended to constantly keep a back-up of all those files on an external HD in case you need to re-install, even on another system.
Transferring between PC and Mac
Make a back-up of both your "My Spore Creations" folder and all .package files within your "Application Data" folder ("Spore Preferences" in Mac) and put them in their respective folders of the new installation on your new system.
Start up Spore and you should have all your preferences and creations where they should be.
The same principle is applied when migrating to another computer.