using version gargoyle v1.4.7 entering my domain, user name, and password for afraid.org after clicking save changes I get a response back from the router: "Update of new dynamic DNS service configuration(s) failed" and "Service(s) could not be updated properly and have therefore been removed."
speculation:
in etc/ddns_providers.conf shouldn't the afraid.org url be "https://freedns.afraid.org/dynamic/update.php?"
rather than "https://freedns.afraid.org/api/?action=getdyndns&sha="
i don't quite understand the other stuff but i'm guessing that's gargoyle doing the sha1 calculation.