Hi, jutis,
Glad you got it figured out.
The display() tag for attributes won't affect what you think; it's just a way to specify that a specific attribute is one that character sheets should display if they have a section to display attributes that aren't the standard primary attributes (if that makes sense).
And no, GCA5 is not abandoned, far from it. References to it find their way into the files exactly because GCA5 is being actively worked on. However, it's a big project, and I have to fit work on it into my days whenever I have free time, so it's taking a while. You can see progress updates as I make them at
my GCA5 blog.