well, about the bugs i found atleast 2 bugs.
this bug is a bit annoying, lot of times when i picked a star and tried to place it in a square it moved to another square near that. I click in a square and it moves to the square on the right or left of that..

another bug, is when u have all the squares filled and the game doesn't finish, u have to click in the main menu button to exit the match.

About the interface, i think u should change atleast the graphic design, i know that u are a developer, but a good product's presentation makes the difference, this happen a lot in the games done in this forum because we are dealing with developers that dont have much knowledge about graphic design.. But the graphic design of your game is not bad, but its not good too, this is just a tip. And its just my opinion...

For example this is the menu interface of the game im working right now, its a simple interface but with a modern style in my opinion...



GL with your project.