1. candy cane>steel>iron/bronze=bismuth bronze>copper>silver>wood
for blunt weapons and misc objects silver>copper>bronze=bismuth bronze>steel>iron>wood>candy cane
2. based on your disease resistance you have a chance to not become a vampire when you drink their blood, you can counteract this by drinking their blood alot; a superior alternative to becoming a vampire is becoming a necromancer, who never has to eat or drink and will remain friendly with humans as long as they don't animate corpses and humans aren't killed by undead around them; vampires, keep in mind, are incapable of gaining physical attributes, and are not automatically brung to the attribute cap upon contraction of vampirisim, they're just raised somewhat high
3. it must've been a necromancer siege
4. its not a bug, you can totally do that, but you'll get a penalty to hitting stuff, just use a longsword or no shield; same goes with all multigrasp weapons, which are totally not large corpses or objects that use misc object user skill
some responses to earlier questions
if you drop an item, it will only stay there if it is on the same tile as a creature's lair or a bandit camp or a labyrinth; if it is not in a creature's lair it will be scattered around the tile, and if you drop it in a lair/labyrinth, it gets scattered around there only instead; but i haven't tested dropping stuff around a labyrinth so don't take me word for that particular part
as far as you should be concerned shops will never have steel anything, and especially not candy cane stuff
the only way to increase your carrying "capacity" is to get more strength or some agility to counter the speed loss, if you're being held down by vanity items that weigh something, such as items that are not gems, money, or teeth, then you can drop them in a creature's lair or something as I'd mentioned earlier