I don't know how I feel about the fact that the last sentence of this lesson was a conditional 😅 I'm traumatized I think.

I agree. He also says "only" is Group 1 when I'm pretty sure it is Group 2. This is a huge difference, as the form for Group 1 is the opposite of the form for Group 2.

You're right! Both statements are contrapositives of each other!

I don't think so, I think the correct order (if you've chosen your premises to be in that order) would be...

4. Sub conclusion: Fluffers is adorable (because we cannot prove he is cute without proving he is adorable)

5. Therefore (because we've proven that fluffers is adorable and premise #2 exists), Fluffers is cute.

I think order of premises does not matter as long as your conclusions are able to be proven in a logical way.

If all A is B

and all B is C

and Fluffers is A, I don't think it is logical to say that Fluffers is C and then using that sub-conclusion to prove that he is B. It makes more sense to say "because Fluffers is A and all A is B, Fluffers is B. Therefore, because all B is C and Fluffers is B, Fluffers must be C.