2) Do dwarves ever actually clean?
YES. Cleaning blood doesn't really seem to work, maybe because it's huge smears that can (as you noticed) cover a sizeable part of the fortress. However, my indoor catapults cause dirt when they hit the walls, that is regularly cleared (although the place is busy enough as it is).
All sorts of dirt / blood / whatever disappear automtically at the turn of season until Toady comes around to make cleaning work as it should.
-what is the purpose of creating artifacts?
You get a legendary worker. The artifact as such is pretty much useless.
4) Will dwarves ever use (narrow) or other such equipment?
No. You'll have to browse through your stocks and have it chasmed every so often. Stockpiles for foreign produce near the cave river also helps, sooner or later stuff will be washed away by a flood.
5) If not, is it possible to have a smelter smelt strictly those types of items?
Yes. You need to designate a item for smelting (just like chasming). If a smelter is told to melt an item, he will only chose among designated items. A stockpile for foreign weapons and armor near the smelters will speed up the process.
--*Name* cancels Store Item in Stockpile: Job Item Misplaced.
It means just what it says: the dwarf can't find the thing he came for. Hauling about and processing foodstuff generates a lot of these messages, and most of the time you can't really find out what happened. May be that something has rotten, but the most common reason (I believe) is that Dwarf A wants to dump some Plump Helmet in a barrel (at the furniture pile) and goes to pick up the Plump Helmet; in the meantime, Dwarf B (who just placed some food in that barrel) takes said barrel to the food pile; Dwarf A finally arrives at the Plump Helmet, looks around, "Where's my barrel?" and drops the job.
[ April 03, 2007: Message edited by: schnobs ]