That's great to hear, I'm glad you're finding it fun!
The scoring requirements for the levels increase gradually, so you can probably get past the first few areas just with your Tetris knowledge alone. But eventually you have to start making more boxes, playing faster, and making clever use of the new mechanics. To finish the sixth area and complete the story, you'll really have to abandon your Tetris instincts and start playing the game totally differently. But it's a fun journey if you can make it!
Best of luck!