Nice, well polished game.
I managed to get to level 5 with score 289.
I don't think you can swap blocks vertically, only horizontally? I was looking for that option at first. But this might have made the game too easy, not sure.
I was struggling at the beginning, when I was figuring out how the controls worked, but the pace was slow enough at this point that managed to figure it out and clear some tall columns.
Then I figured out a "cheat" to "swap" only one block from top of the column to go lower and built matches this way. Nice realization of how the game rules work when it clicked.
Nice, clean art and pleasant music.
Cheers!