I've found out how to change your main dark goo ball to any kind you want. For example Ivy. Here is a improvement that it actually works (If you can't open the page, quote and copy the link and paste it in new window).

If you want to do such a thing as this follow these instructions:

1. Make or find a cool image you want your goo to look like.
2. Go to your PoG folder, res/images and fins an image called default_GooBall and delete it, or cut it and save somewhere else.
3. Copy and paste or cut and paste your made up or found goo ball picture and rename it to default_GooBall (Picture must have the same id as the other images).

Then go to your game and enjoy playing with your own made up Platforms of goo ball. I suppose you could do the same with other features.

Any questions ask here. I'm visiting goofans really rarely now but I'm getting smarter.