I've had a long break from the game, but I jumped back on as soon as I got home on patch day.
I made a new world, and found a big cave in the side of a mountain and decided to build a town in there. Well really it was like 2 big mountains with overhangs connecting in the middle. So I threw some cobblestone in the oven and used that to fully connect the two mountains and close off the back (except a for a door leading out back there). I put a wall with ramparts blocking off the massive opening so I don't get enemies wandering in. I've got a mine in there too, which leads directly into a natural cave I've pretty much mined out for metals.
I went exploring yesterday, in search of pumpkins (which apparently are bugged, and spawn as pre-carved jack-o-lanterns). I found none, but I did find a huge mountain (the trees on top touch the clouds) in what I think is a tropical climate. There's TONS of trees, and the mountain overlooks a cool bay and has some nice cliffs around it.
I have the materials to build a portal to the Nether (hell), but haven't done so yet because I keep getting distracted working my town. I want to make a portal at my home base, and at the mountain in the tropical climate area, and then hopefully connect them with a path. Apparently cobblestone is impervious to ghast fire, and the ghasts can't see through glass. So a cobblestone path/bridge with glass windows would make it safe, but let me see the environment as I pass through.
Oh and Idol, the portal thing you mentioned is a bug that has to do with the way the game checks to make sure you're on a good spot to come out of. When you make your portal, it places the one in the Nether somewhere that hopefully won't drop you in lava or off a cliff. What it's doing now is when you exit back to the normal world, it's doing that check again, and not paying attention to the portal on the outside that you placed.