Did you know that the Jim Henson Company had a plan to adapt Borgel into a Muppetish production? It’s true, at least according to Muppet Wiki.
More interestingly, there are a series of production paintings made for the project by Wayne White. You can find them here (first 4 out of 19).
“Borgel” Production Painting, Jim Henson Company
Thanks to Jim Windisch from the Daniel Pinkwater Facebook group for finding this!