The business about the ring.....Maggie was counting on an awful lot of luck here. She was hoping Willie just might sell it to someone she knew, someone who would recognize the ring as hers (not very likely). The other option is he would lose the ring somewhere (preferably outside the Old House and into town) and again someone who would know it was her ring would find it and realize she's still in the area. Only problem is that Willie could indeed lose that ring, but he could do it almost anywhere, like inside the Old House where he or Barnabas could stumble across it. She lucked out when the ring fell out of Willie's pocket as he tossed David out of the house and then David found it, but struck out when he showed it to Vicki, who then showed it to Barnabas up at Collinwood.
Well, desperate times call for desperate measures.
When the police eventually get around to [spoiler]searching Willie's room in the Old House, they do find this ring (with a lot of help from Barnabas, but I digress), and Sam immediately recognizes it as the one Maggie was wearing when she disappeared (though as Robin mentioned, we saw she wasn't wearing it that night, but I digress again).[/spoiler]
Had Willie not lost it, I suppose it's also possible that a future owner could identify whom it belonged to based on its inscription, or, since Willie behaved nervously and even recklessly enough for his middle name to be "suspicious," the sheriff could have found another excuse at some point to search him or his possessions and come across it, so I think Maggie had a smart idea, but unfortunately for her Barnabas was smarter... and luckier.
What a great excuse to include Vicki and David in this arc.
It was far-fetched that someone who knew Maggie would see that ring. But cudos for her giving it a try, anyway. She's a fighter! <big ok>
And just when we see that the girl still has spunk, we have to watch Barnabas use her efforts to demoralize her further.
I would bet that in 1967, I was riveted to my seat, wondering if Maggie was going to escape or be killed.