I can't seem to open your capx. Anyone else getting a grey screen?
I'm sure others here will have better solutions, but you could do something like add an instance variable called "Order" to your number sprites, then give your first box "1", your second "2" and your last "3". You can then have a condition that says "Sprite instance variable is = to 1" or 2 or 3, giving you the box you are looking for (so it's like manually setting and picking an ID).
The actual number could be a global variable, so you can say "start global variable at 1", then do the the "where sprite instance variable is = 1", do your animation and then increment the global variable by 1 to 2, then the last number sprite after he has done his animation can set it back to 1.
<img src="http://i.imgur.com/FM9TE.png" border="0" />
In the screenshot above I'm setting the next number box ("CurrentNumberBox") in the same area you would have the animation run, but you could easily move the part where the block collides with the player.
I'm not sure if I'm making myself clear, but it might be enough to get you started :)