You aren't going to like this...
Cheat Engine isn't made for "games" like Cafe World. Cheat Engine is made for games like Quake, and Doom, and Fallout 3, and FarCry and Crysis... single player games you install on your computer. Cheat Engine examines the game as it is running. From the website...
"It comes with a memory scanner to quickly scan for variables used within a game and allow you to change them" ... this would apply for games where you COULD go to the local file that exists with the game installation directory, and then change that game variable to something making the game easier.
The game Cafe World doesn't install to your computer. It is a flash-based game where all those files that contain the game variables reside on a central server... out of your reach. You can't make changes to the game in order to be able to cheat.
So, I'm sorry. Cheat Engine can't be used for what you want to do.
Most importantly, questions like this should be asked on the Cheat Engine forum, where people who use it regularly could answer your questions in more detail... or you could find out for yourself it it was possible to use it for Cafe World by seeing the kinds of games it *IS* used for
http://forum.cheatengine.org/
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