Watch your language! Its Groups not Group! Its plural biatch!
Fix Add method template. Pass modules and permissions.
No sense in editing Administrator permissions. They can do anything.
Makes more sense if Group::findManyInId() returns a collection of group models and Group::findManyGroupOptionsInId() returns a flat array.
Fix editing groups
Awww shieeet!!! we can assign multiple groups to a user! There is some logic in place to prevent an administrator from removing his own super group but needs more thought.