Glitches I found:

While entering/leaving the "bonus" room and clicking away at the same time causes your mouse to be stuck, you can fix it by pressing pause, clicking away from a game and resuming the game again.

At the third bonus room of first level I got glitched and flyed through the floor and finally died without being able to do anything.

Every time I finished the third room and left it, I died due to the floor glitch or I just lost everything I gained from the room and was able to come back with all the gold still being in the room with the enemy and all the gold I collected previously before entering the room was lost.

I stopped playing, after those room glitches. Maybe it would be better later, but I kinda got bored due to the glitches.

Pros:
-Graphics and movement seem to be much better than most games.
-A volume control means I can turn down the overbearingly loud audio (not your fault, I think every flash app does this), and normalize it with other stuff that I have running.
-The XP/shop system is nice, but could be a bit cheaper on the coin purchases.

Cons:
-Some places it seems that I get killed when it doesn't appear that I touched the thing that killed my character. Spikes on the ground, for example.
-It took me awhile to figure out that the gun is mouse controlled. There is nothing in the options that tells you how to fire the gun.
-It is sometimes difficult to judge where to place my character on a jump when he moves off the top of the screen.
-Sometimes when moving from room to room (through a door), he gets stuck off the screen and the game appears to freeze.
-Some enemies can be squished from the top, Mario style, others can't. There is no intuitive way to guess which ones will die and which ones will kill you, aside from experience.

Graphics is the best
But it is glitchy like hell

Seems like this needs some more play testing. First level there were several minor glitches with randomly restarting from checkpoint, when I entered the pipe world i fell right through the floor, and again when i entered the regular over-world. For the other aspects, it looked like the graphics, sound effects, and layout had good potential. This is just an unfinished product for now.