I don't know the Zygor add-on, but if you want an add-on that lists the quests you have and haven't completed, I recommend Journal Quest Log, which is based on the quest database maintained by UESP. Doesn't guide you through the quests themselves, but does show you if you've got any left to complete in a zone (as long as that quest is logged in the database, which most are).

its been a month of using zygor..

i have figured out some quests that have multiple responses influence future quests into the zone you are in..this is what i didnt like about just going at quests willy nilly. there some quests one wont be able to do based on how you responded earlier in prior quests. I am unsure the zone or npc but its an earlier zone..you get off a boat and there should be an npc on the docks sitting on a bench. I noticed zygor telling me how to answer so i did..i dropped the quest and picked it back up and answered differently..that npc was now gone and i was being led somewhere else.

i also feel zygor just goes through the main story of each zone leaving some side quests to be done on your own. so therefore i do what zygor suggests and then i feel i am getting more quests done picking up side quests later. i think it does just enough to unlock other quests

manually stepping zygor sucks, i wish it would just do it automatically all the time.

when you come to the end of a zone its obvious that zone is done as the noise the addon makes it quite annoying.