Simple platformer with very little to offer
First thing first, this game is unplayable on Mac OS X or at least on my Mac (OS X Leopard, newest Flash player, didn't work in either Chrome or Firefox), because the controls do not respond to input. Whatever code you may be using with Stencyl to get the controls down, get/code something better. Get a play tester with a Mac to see if similiar issues arise in future games of yours.
Well then, what's the good stuff in here? The controls (when they work) are nice and responsive, and you've got nice control over the character's movement. The collision detection works pretty nicely too, so it's player's fault when they mess up, rather than the game breaking down. Also, the graphical style is nicely simplistic, so there's little to complain about.
But the bad thing is... That's pretty much it. The game itself is a textbook example of how to make a generic platformer. There's next to nothing new here, and this kind of game simply has been made before sometimes even better than what's shown here. While it works for what it is, Newgrounds gets introduced to games like this pretty much daily so it's harder to find anything that sets it apart from others. This is one of those games that you easily forget right after you're done with it, or even while you're playing it. The only more "fun" part was the boss battle at the end (which felt kinda rushed given how lazily the Santa bot seemed to be animated, and how it simply walked through things and then randomly fell to oblivion), but that doesn't win it over. The soundtrack works to the game's disadventage, as it feels just about as generic as the gameplay itself. The music loops so much and it's so boring to listen to, that by end of the game I was getting sick of it. More variety on that ground, aswell as gameplay, would be very much appreciated. Also the cutscenes are boring to watch, so one could simply skip 'em because they don't miss anything notable for doing so.
When I happened to stumble upon your Twitter (and from there play this game), I noticed you said that the reception here on Newgrounds has been kind of slow because "people don't like challenge these days". It's not that, because this isn't a challenging in a way or another as it's just a boring blend of trial and error.
I decided to give you four stars. Three of which are for the graphics, and one for the technical aspects. I could have given you more, but with the inability to play it on Macs and the fact it's made with Stencyl (in other words, you had to do less yourself) I decided to only give one. The soundtrack doesn't win a single point in my book for its repetitiveness, and the used sound effects don't make me give it any extra points either.
I'm not familiar with Stencyl, so I'm not sure what it allows you to do and what kind of limitations it has, but I'd really suggest you to pair up with a competent programmer and/or learn Flash programming yourself. I'm saying this because you've got promise, but you'll need to step up your game and make something more interesting or fun if you want to make a bigger impact.
Don't mind it if this review stands out as a big speech of hate to you. What I'm trying to say here is that you should try and experiment with something more complex (and possibly more fun) things to create something more noteworthy or enjoyable.
Ps. One thing that irks me is that the jumping animation is the same as the used for running.