Thank you The hard part of designing circular quests is that they're all going to be "post-game" material, intended to be very difficult. Daggerfall's engine doesn't lend itself to difficult quest instances, since once you can beat vampire ancients and daedra lords, the only remaining threats are human beings, and just spamming Nightblades seems like a silly way to increase difficulty. Some difficulty types will depend on spell effects being activated.
If you want to try interactive quests, you can try my Perpetual Quest system. Right now it has 15 quests plus the entire Cartographer system running, which adds about 16 more quests. It's a system that makes Daggerfall keep coming back to you for more adventure, albeit at varying degrees of difficulty. You can use the console command "startquest JHPQINIT" to enter the system.
If you want to try post-game level content, I made a prototype of an introduction to a circular quest called "Death's Embrace," which uses the quest ID JHMG00X. You can use the console command "startquest JHMG00X" and check your journal to see what dungeon it sends you to to begin the quest.
The Quest Showcase topic is where I've posted the download link for my quests.
For all talk about quest development - creation, testing, and quest system bug diagnosis.