I figured out that because of the way it was programmed conbined with the illogical coding, it was impossible for me to 'fix' the scenario from its current state. It would be better to re-write the whole thing (for me, at least).
For example, I would create a seperate class for the TPlatform object (instead of using a Rocket object and changing its image). Also, I would create one Rock object at the beginning (from the world class) and use its location to determine if (1) it is moving and producing tail fire; or (2) it is stopped (has landed) and is not moving or producing tail fire, and should have a crater around it. Also, I do not think I would have used to Animal class as a super class for most (if not all) the classes you used it for. Another thing I noticed is that the counter objects displayed at the top left of the window is part of the background and not an actor.
If you stop the scenario just before it goes into the MainMenu world, you will notice that there are two instances each of the following classes: Rocket, Rock, and Text.
If you want, you can re-write the code.... I can then see what you wrote for future things. How do you think my programming is for a High-schooler that started Greenfoot in January?