It seems I made the Round World level too difficult. It will be toned down in the final release, so there is less randomness and things of that sort.
Speaking of difficulty, the game won't feature a hard mode, but I have thought of a way to add a sort of challenge mode to the game. One of the unlockable characters will be called "Blocky Dude", and will essentially be a cheap rip-off of Blocky Man. Blocky Dude will move slower, and his jumps will not reach as high, so the game will be more difficult when playing as him. On the other hand, you'll also be able to unlock Commander Awesome, who runs really fast and jumps really high. Finally, you can unlock Stompy, who is able to shoot enemies.
I have to actually program the shops first before implementing any of this.
I did start working on level transistions though:
Jumping on the button and raising the flag signifies the end of the level. In the final game, when the flag reaches the top, you're score and rank for the current level will be shown. You'll still be able to move around as Blocky Man while the score is being shown, but Blocky Man can't leave the screen at that point.
Anyways, I'll work more on all these things in the coming month, and maybe be able to release the game next month.