Hello!

First, the boxes at the bottom. Those are the Brain and Brawn scores. 

In the book, it looks like this in the rulebook, which i should update. Basically, sometimes you might roll a check against your Brain or your Brawn as a whole, so you add up the middle number to count as that stat.

As for the two extra stress boxes, in the current rules, there are two roles that give you an extra stress box: Tank and Trooper.

Let me know if you have other questions! And let me know how it goes!