Wow. Quite a quiz, there, Rob.
Gosh, I recognize most names but cannot place them. Is identifying the story (in the less obvious cases) accepted as a half good answer?
Name an ocean channel near Duckburg. Name the "Straits". Name two bays. Name two coves.
Codfish cove.
Name an island inside the Duckburg Bay, or the sound in which Dukburg Harbor is located.
A typo makes this one even more difficult.
Where is Pumpkinburg?
Where was Dizzydrop Hill?
In such questions, do you mean "North? East? ..." ?
Pumpkinburg is upriver from Duckburg (they race to there on the frozen river), so it cannot be West.
What real estate did Cousin Gus own? Cousin Cuthbirt Coot?
I believe Cuthbert Coot is the one who owns a dude ranch; in an early ten-pager ("The Limber W Guest Ranch"?), Donald visits him with the nephews to show them how good a cowboy he is-- and ends up practicing on their hobby horse at the end (which gives me an idea for another Theme Quiz: books in Barks' stories).
What school did Huey, Dewey and Louie attend?
13th 1/3 precinct school?
(I am sure it's "13" and there is an odd fraction.)