Sorry about that. Should have looked over my wording in a different perspective. It was a very douche-y thing to say.
@TailsSena: I apologize for my rude behavior, I'm not usually like that. =/
Here's somethings I have found when playing your demo that could be improved (if you'd like):
The player seems to accelerate to fast, could you slow it down a bit? Maybe make it so if the player goes higher than certain speed his acceleration increases.
The jogging up to full running appear all one animation. How about splitting them up into separate animations and making each one play as the player reaches a specific speed. So the player wont go from the full running speed back to walking if it's going slow enough.
Increase the speed of the jumping/ rolling animation just a bit. (You could even make it so the animation speed increases the faster Sonic/Any Character is moving. I think it can be done one way by setting the animation speed to abs(xspeed("player")*a number) while action = jumping.)
For level design, I suggest you try to make the level in small/medium sized chunks. Or draw out a basic path for the player on some paper, then create separate paths (some having more platforms, others being more loopy, but still take around the same time to pass as the platforming.) Then try to replicate it in the program while adding decoration as you feel necessary.
Waterfalls are lovely, aren't they? It would add a boost to you levels design. Add some rocks , flowers, and maybe shrubs around the falls. A bridge across would be really cool to see as well. Perhaps some smaller waterfalls near by? Just giving you ideas of what you can do with an area to make it look full.
The location of these special decorations are important too. Putting them in an area where the player just goes by really fast would be a waste. A good spot to have them would be in a platform-y section, where the player is going slow enough to notice what you have done. For speedier sections you could space things out a bit more, and add bigger things. Trees, for instance. Or perhaps some bigger bushes.
For the logos: splicing them together is not a great idea, it can damage the quality and look a bit odd. If you would like the source of the image, just ask. If you'd like a more specific request, make sure to supply the smaller details. (I know I just did it for fun, so I'm not aiming this towards my work.)
I hope this helps you with your game. I'll be looking out for another release.