Interesting demo! I had to stop after the HUD started drifting all the way in front of where I'm placing things, but the concept is fun. It has a lot of strategy to it!
The jackpot sound that plays when the three tiles match is quite loud.
Most objects aren't aligned with the pixel grid, and several objects are rendered beyond the 160 x 144 resolution, especially the blocks inside of the slots.
All-in-all, good work! Congratulations on the submission!