In light of the insane problems that people are having patching recently, I hope I can catch some people before the go crazy and/or delete the game.
If your game says "version incorrect", you'll need to patch the game. When you get to the screen that lets you change window size or pick full screen, you click the "patch now" button.
For people whom patching in taking way to long, I don't know what I can say other than to agree that the process has become horrible of late. The time it takes people is varying incredibly wild and it's taking some people longer to patch the game than it took to download the quick install.
Kittynator has said that re-downloading the game using the full install found at http://www.hellokittyonline.com/redirect/download_full will be faster overall. It will take longer to download the game, but in her experience it needs less patching and may take less time overall.