Scripts for beginners.

How do I set up a Prophet's Hut so that I can take and complete the same quest multiple times? I set it to "Bring creatures." The reward gives other creatures. I take the quest, deliver the required creatures, receive the reward, and the quest is completed. But I can't take the quest again, even though I've set "Quest.CanUncomplete" to "true" in the hut's settings. What am I doing wrong?

Also, if I assign the same group to both a Portal of Water and an Underground Passage, will they conflict?