Author Existence Failure: Many fans have hoped Rosa would sometime write a story bringing Scrooge and Goldie back together, if even for just a special, considering he often left hints for it. That, or merely that he'd be writing more stories in general. Because of his retirement due to various issues however (see below), it doesn't seem likely.
Doing It for the Art: Very much so. Don Rosa's family ran a successful construction company and he was an engineer before turning to writing and drawing comics, which meant a major pay cut for him. Disney pays a flat rate per page to their cartoonists and no royalties, which meant Don Rosa was paid even less than most due to how slowly he works with the amount of meticulous detail he habitually inserts to his drawings. Despite all this, he laboured for decades like this, not compromising the amount of detail or attempting legal action to improve his financial situation all for his love for the craft and the fans. Of course, things finally did get too much for him as you can read below...
Fandom Nod: The Quest for Kalevala is one for the Finnish fandom.
God Never Said That: Don Rosa has debunked the often-referenced notion that he hates DuckTales, and has said that he actually regards it as one of the best animated series of the late eighties and early nineties. He, however, clarified that he just doesn't think of it as a definitive version of the characters it depicts and is annoyed when he is mistaken for a "DuckTales cartoonist" in conventions in America.
Missing Episode: "The Starstruck Duck", a comic by Don Rosa that didn't go beyond the sketch stage.
Screwed by the Network: Due to the way Disney Comics distribute their revenue, he never got a single cent of royalties for any of his comics (nor did almost all the other Disney comics artist, Carl Barks being one of the very few exceptions). His work is incredibly popular and bestselling in Scandinavia, yet he only ever barely scraped by financially due to his wife, who earned a higher wage, supporting him. The only payments he got for his comics were one-time payments per page, which meant a very meager hourly wage do to how meticulous and slow he works on all the details. At some point he trademarked his name and asked the publishers for at least an small yearly fee to use it prominently on the covers of Don Rosa only paperback books. He also got some money for signings he did, but those paid an even smaller hourly rate than his comics. This appalling treatment combined with his deteriorating eye health led to him eventually becoming depressed, losing all passion for his work and retiring as he explains in this epilogue to the Don Rosa Collection, which Disney refused to print, resulting in him putting it online for everyone to read. Nice Job Breaking Him, Disney!