On the question of the 4th string being tuned an octave higher than one would normally expect:

This is what is called "re-entrant tuning." Some Renaissance and Baroque guitars were tuned this way (the young lady playing the Baroque guitar is a Seattle girl, by the way).

The Renaissance guitar was the first instrument to be called a "guitar." Not a "kithara," "gittern," or other variation of the word. Both instruments are strung in what they called "courses." Doubled strings, like a 12-string guitar, but with the top string (i.e., the highest in pitch) was single, and called the "Chantarelle." The lower pairs of strings were sometimes tuned in unison, sometimes in octaves. And sometimes they were tuned an octave up, like the fourth string of a ukulele.

The Renaissance guitar has four courses and is tuned like the top four strings of a modern guitar (with the possible octave variations as mentioned), and the Baroque guitar has five courses, like the top five strings of a modern guitar (also with octave variations).

As I said, this is called "re-entrant tuning."

I'd love to get my sweaty little hands on a Baroque guitar, but a well-made replica is pretty pricey.

Whether a ukulele is a toy or a musical instrument depends on who happens to be playing it. It has the potential of being a serious musical instrument.

After all, a violin has only four strings.

Don Firth