In my game if you go through the unfinished tutorial, you encounter three problems:
1.) You have to click food twice to get it to work, which means you have to click food again after it disappears.
2.) You have to do the same thing with store, clicking it twice.
3.) The OK sprite won't disappear even though I have it set that if tutorial # doesn't equal ___ then it's supposed to hide.

Here's my game link:
http://scratch.mit.edu/projects/11585372/

Please try to help. D:

Sorry, just realized it seems to be even more buggy in Scratch 2.0 than Scratch 1.4, (which I use).
Here's a new link:
http://scratch.mit.edu/projects/11585555/

Edit: Food disappearing problem seems to be fixed in new link, but other 2 bugs are still there.

A game will only be slow if there are too many scripts running in unison. I wish I had time to look at the project and give you specifics, but a couple really big scripts, or a lot of smaller ones will cause unresponsiveness, and bugs. Found that one out by trying to create an AI… The best way to deal with it is to shorten some scripts, or just ensure that the scripts are only running when they have to. To do this, use broadcasts as your hat block, and a repeat until as your control.

Okay thanks, I'm not sure where I could cut some scripts short though.

Okay, I'll see if I can look more at this later, I'll try to help.

Okay thanks!

I fixed a few bugs in the game. The new version is now uploaded here:
http://scratch.mit.edu/projects/11589335/

Now it actually seems to work better in Scratch 2.0 than Scratch 1.4. So strange… Haha