Due to a change at Google Maps, my add waypoint script needed to be tweaked as someone pointed out in my original post about the userscript. It has been fixed and seems to work again.
Additionally, I decided the [DeliciousSort Delicious sort userscript] would be more useful if it were toggleable, so I implemented that, admittedly not extremely neatly, but it works. Reinstall the script if you want the version with "sort" and "unsort" buttons. It still sorts by default.