There's more trickiness involved here. This stage is also harder than the last ones, so be patient. Head to the right and jump over the two square enemies ahead. Use the elevator to go up and then destroy the flashing brick to the right when you reach the top. Now head right, destroy the two flashing bricks ahead, use the elevator, and then enter the door. When you reappear, jump to the left and enter the next door. Use the elevator beside you and then head through the door at the top. Carefully, make your way down the descending platforms and enter the door there. When you reappear, go left and enter the door. There will be a ball waiting for you near the door so kill it and then destroy the flashing brick to the far left.
Enter the door again and then head up the elevator to the right. Kill the ball at the top and use the elevator to the right. Wait on the left above the door you seen on the far right. After the elevator drops, the square enemy will float to the left. When it does, jump down, stand roughly on the middle on the rightmost platform before the gap and then jump toward the door. You can't jump from the edge of this platform because the platform above the door will stop you and you'll end up falling back down onto the elevator. Enter the door once you make it. When you reappear, climb the ascending platforms, avoiding the square enemies going up and down.
At the top, avoid stepping on the platform to the left of the door above you. It will disappear if you do. Kill the ball, jump to the left, and then use the elevator. You're almost done at this point. When you reach the top, stay here until the balls bounce to the right. After that, walk to the right and destroy the balls but don't walk onto the stack of platforms above the door below. They will disappear as well and you'll have to climb the tower again. Go to the far right and wait for the purple molecule to appear level with you. Let it hit you and you'll fall to the platforms below. Now all you have to do is walk to the right, jump onto the elevator and enter the door to finish the stage.