Thanks for spotting these, I really appreciate it!
1) This was deliberate to make people think about the word being formed ;)
2) Good catch! and again for 5)
3) Yeah, this is a nod to super nerds. If you give it a google you can find it in various compendiums.
4) Again, deliberate to make people/kids think about the wording and their general knowledge. Sirius is often called the 'dog star' - I'm being a little facetious with 'canine' as an option.