They won't be possible. That picture I sent you before - all that was possible then was mounting it and sitting there. They never did anything more. Sorry.

then MAKE them do stuff

No.

The game is done. Other than possible bug fixes, I will be doing nothing else to it. Plus, as said below, it's not an easy task to make them do something worth doing.

Adding Yoshis would be fun, but it seems like that would be really tough to implement, considering the amount of programming and sprite work that would be required.

Miles, Why Not make a game called Yoshi's Island: Just For Fun

I don't have the motivation to do something like that.

As for the PS3 controller, to get it to work, do these, in order:

Settings 1 > Other options > Customize controls > Player 1 > PS2-like controller (be sure to pick this)

After that, use the controller to navigate back to the first menu - then try battling. If the buttons are anything other than this:
X: jump, select something
square: run
circle: kick

then try using the Xbox 360 controller setting - remember, those settings only affect what buttons do what, you can use one controller with another's settings but it'll just be weird.

When I make it the PS2 Like, None of the buttons work. And I don't have an Xbox 360