If it's free, I think you should also upload a .dmg of your game for those who don't have Snow Leopard. Yes, I know people who don't.
As for your game, I've written a little review!
- Really slow to load on my really recent MacBook.

- Lags at startup
- Great graphics! Really good graphics!
- Don't use the mouse so much for killing enemies! More on this later!
- Err, lots of lag in general? I think you're pushing Game Maker too hard.
- Unibody polycarbonate MacBook here, with a 2.26GHZ Core 2 Due, 2GB of DDR3 RAM, Nvidia GeForce 9600m (256VRAM)
Review:Ok, so I started the game up, loaded (took a while), and started a new game. Movement is pretty good, if a bit slow, and I think the idea of dragging cubes to change your environment is pretty great too! Mostly what I didn't like is that the lag (or the slow motion you set the dragging/moving to) doesn't really let me move and hinders me. So I think you should increase both of these in an update.
One thing that really annoyed me about your game is that you have to click to kill some enemies. Apart from the fact that since movement is slow it's hard to evade these enemies, you have to consider that this is a Mac game, and Apple sometimes gets too... innovative with their mouses, and that can hurt gameplay. Since I'm on a multitouch MacBook, when I click, the mouse freezes. This doesn't sound so bad, but it really translates into really annoying and repetitive gameplay. The general lag didn't help.
I made it to the ice level, in the part that you have to shrink your Cube, and to be honest I just got bored and quit.
I was kind of thinking why I didn't enjoy this as much as identical concepts like Super Mario, and I realized it really boiled down to the flawed movement system you've got there: it's a bit prone to sticking your character to walls, it's slow, so I guess you end up getting annoyed because of it.
I'll be updating this review as I notice more stuff.