This game really needs a relaxed mode. The levels that steal your shapes while you're already rushing to play are particularly frustrating. The time goes by way too fast. Also, the match 3 game in between some of the levels is unnecessary.
I was looking for a nice relaxing and challenging tangram puzzle game. This was just frustrating.
Windowed mode would be nice too. From a programming perspective, they at least did the full screen mode properly. They waited until they got their own screen space before changing the resolution. Games that change the resolution of the desktop before creating their own screen space are very ill programmed and inconsiderate to the user.