Thanks for your questions! I will reply here and move these to FAQ in a while.
1. How do you get more energy for your pets?
Pet's energy replenishes with time, 1 energy point every 24 minutes (full energy bar replenishes in 4 hours). Right now there are no ways to increase maximum energy more than 10 points. The other ways to replenish energy are Energy Poition (premium item) and Sanctuary (building).
2. Can un-shared custom skin designs be sold for Silver Coins and/or Gold Coins?
No. To avoid problems with copyright, user can upload only his own artwork. We plan to introduce another feature which will help authors earn more profit from their skins: you will be able to set a price for using your skin. Users who would like to use your skin will pay you this price.
3. Does sharing a custom skin make it available for all users with a Rainbow Jar forever, or can a skin be retired?
You can make your skin private (this means it's available only for your pets) if it wasn't used by other players. If it has at least one public use, the skin will be available forever. If you want to remove your skin from the List of Custom Skins, please send request through Contact Us explaining the reason why do you want to remove it.
4. Must skins be of the entire pet, or can it be an edit alone (such as positioning extra horns on a dragon and then making everything but the horns transparent)?
The skin should contain the whole pet. It won't be placed as a second image overlapping standard skins but will completely replace the image of the pet. Although you can use official skin base and add the modifications which you would like to see.