Off the top of my head, if you're talking about the skeleton guy being troubled by a demon, you find one of the ritual murder scenes like the one upstairs in the phoenix inn (hell, it might even be that exact room, can't recall) and you should see some unlit candles around the circle of blood. Light them and a demon will appear. Mindread and kill him and his blood will automatically be in your inventory. Give that to the skeleton dude and he should be cured.
As for Caracalla's Revenge, remember to loot his key off his corpse in the market area for a chest in the last room. As for actually progressing through the house, the key is lighting the candles.
For Wild Willows, I believe that's the Asylum? It's kind of tricky. I actually missed this on my first playthrough. After you enter and make the first right and come into that large hall, go left and you should see some pressure plates next to the wall. Step on one and nothing will happen. Try to leave the way you came and a bandit will threaten you. Propose to work together and he'll stand on the other pressure plate, revealing a new area. Or you can kill him and loot the key to the cage in the first room. You can then free that guy and have him stand on the pressure plate.
For the chest outside, I'm not sure if I'm thinking of the same chest you are but if it is, facing the front of the chest go right and up and the wall should make a little corner where the key will be laying.
As for the final aerial battle, remember that the game automatically unequips your dragon armor and gives you no-stat bone armor. Your original dragon armor will be put in your inventory, I suggest putting on the chest and legs at least for +40% offense/defense and HP/MP. For strategy, I honestly just focused on destroying all the towers, got way ahead of the zeppelin and finished with no damage done to the zeppelin. Just remember to attack nest towers first, summon your wyvern and use wrath of the patriarch only on large clusters of towers. Oh, and remember to destroy every single ballistae before moving on to the next group of towers. With the slow speed the zeppelin travels at, you'll have plenty of time.
I can't recall what was with Luxurious' chest, but I'll hop back ingame and see if I can remember.
Edit: Actually found the answer to this one in another thread. Apparently if you take Tom's finger and get in that way, the general will open that chest for you. I've never taken that route (always went in through Taurus' house) so I wouldn't have known that. Amazes me that no matter how many times I play through, there's always something new to discover.
