I got it working (the best I can tell based on your very vague description of game play and progress thus far).
It at least now spawns level 2 as desired and it stops when it hit level 1. You had an of-screen block for spawning level2 so it fell into the game on mouse click, I moved it off screen so this didn't happen.
One thing you need to consider, block alignment is going to be your main problem. If you remember in Tetris when you moved a piece it moved in grid increments (which was part of the fun.. tap, tap tap, drop).. you will need to create some way to make sure they are aligning correctly. I will get back with you if I think of an easy way.
If you made sure all objects spawned at block width increments and instead of bullet to move you used a move-object-x-pixels (width of 1 block) at a time it might work.