The “Change Ancestry” button doesn’t appear to work when building a character.
Thanks! We’re looking into that! 
Interesting bug. If you click the change ancestry several times in quick succession, it will apply the base bonuses and penalties to the base stats. I have a zero strength, 19 int/cha character.
Once you click the change ancestry, you can no longer change any of the other options for the ancestry previously selected.
Very interesting.