Not sure if this is even possible to undo "Completed achievements" if I were to accidently have one selected when I go to recalc. The only work around I have right now is to Save my profile data everytime I tick off an achievement, so when I do tick one off by accident I can close the window and reload the save that has it unticked.
This is already possible by removing the achievement in question from the "Qualities" tab of the player table and recalculating. I have added this to the readme file.
Not sure if this is even possible to undo "Completed achievements" if I were to accidently have one selected when I go to recalc. The only work around I have right now is to Save my profile data everytime I tick off an achievement, so when I do tick one off by accident I can close the window and reload the save that has it unticked.