Hi!
Sorry my for the lack of Mac build, no one of the team own one, and since we cannot test the builds we decided to not do any for now.
Yes our dice a fully physics based! It was important to us that the dice behaved like real dice, there is also no randomness fudging going on, just pure dicerolls.
If you want to I can do a small write up and some pointers on how we implement the dice?
Curios to know which YouTube video you found us in :) - mind sending a link?