The rules of WFRP4e were never the simplest to begin with, and they’ve been gradually revised over a number of supplements. In order to get my head round the Group Advantage rules in Up In Arms, I made myself a cheatsheet which you can now find in the 4e Downloads section, here.
The Daily Empire
An Inspirational Blog for Warhammer Fantasy Roleplay
Nice job. Also about the right font. I will take it as the template for my own because my players developed their own Advantage uses with all abilities.