this topic is raised from time to time and always got unanswered from any MikroTik personel: http://forum.mikrotik.com/t/feature-request-tool-dns-update-for-aaaa-and-other-records/84542/1 http://forum.mikrotik.com/t/add-remove-reverse-or-any-other-records-using-tool-dns-update/88376/1 etc.
I want just to give my five cents, I also need the possibility to remove expired records and manage reverse (PTR) and TXT records.
Only thing I can’t understand why this isn’t possible from very start. Almost all code is in place, developers only need to implement encoding other types of RR in addition to A, which is not very much work.