As a preposition, below would be written after information as a stranded preposition.
While typically prepositions would precede the noun, stranded prepositions can occur in.
I think this is a question of elegance, rather than correctness.
Starting a sentence with however works fine - but in every case i've encountered, putting it in the middle adds punch.
There are several questions in this question.
I don't know if there is a specific term for these words.
I'll say region words for now.
As for a list, i can add barony canton city commissary.