I was just curious about whether or not I can drop Quest items when I'm done with them? I currently have many, many keys in my bag of holding and numerous assorted items such as the rituals and sun emblem from Umar Hills. Can I drop these in a particular shop someplace and not lose them? (incase i need them later on) I never did figure out what the Amuanator Emblem was for, I tried clicking on all the alters and such but nothing happened that I can tell. I plan on keeping certain items such as the shadow dragon ward, it might come in handy later on, I don't know...

Rogue, Did you kill the Shade Lord in the Temple of Amantaur yet? I'm pretty sure the symbol is supposed to disappear when you open the door you need it for.

You're generally pretty safe dropping used quest items. However, to be on the safe side, you might want to find a place to stash your items (the same applies to surplus gear). Most items will disappear (find new owners) if you leave them lying around. IIRC, this doesn't apply to critical quest items. But, to avoid problems, find a container in an empty building and stash your stuff there. There are many throughout the city. One caveat - don't choose a place that is a future/potential stronghold area because you stand the chance of losing the items for good if/when the area becomes your stronghold.

By the way, if you have completed the Temple Ruins quest, then you used the Symbol of Amuanator without knowing it (which often happens with other keys as well).

Uhm...I believe the shadow dragon wardstone has its purpose, it will protect you from the shadow dragon, that means he will not turn hostile on you, unless you turn hostile on him.

If you're not familiar with the purpose or function of an item, it's a good idea to hang on to it and dump it into the big stash of all your other miscellaneous items you don't know what to do with. Then, if someday, you discover a need for that object (such as a locked door or some upgrade that uses that item as a component), you can just go rooting through your stash, instead of hunting back and forth across Amn going, "Now where the heck did I drop that key."

Later on, you'll learn what to keep and what can be got rid of.

I'm thinking I kinda did it backwards, because I killed the Shadow Lord before I even went down into the Temple, and also the Shadow Dragon died a minutely painless death, while I lost 3 of my party members in the end of some 20 tries at him (eg). Only to find out there were items I could've used. Also, is there a part 1 to the journal I found in there? I have part 2 and have checked every location I could find twice, but nothing.

IS that even technically possible? Don't you have to go down through the temple past (or through) the dragon and then fight the shadow dude? How does one defeat him without even going through the temple?

Doing the Temple Ruins backwards might actually be possible, but I've never tested the theory. After you kill the Shade Lord, the map changes to one that's virtually identical--the only changes are the statue of Amaunator, the fountain....and now there's a little path that connects the area where you fight the Shade Lord with the rest of the map. Therefore, it's possible that one of these scenarios happened:
A) Rogue_At_Heart hit a weird bug in which his party was sent to the "daytime" Temple Ruins map instead of the "nighttime" one, and was therefore able to walk right up to the Shade Lord and say hi.
B) Through some weirdness, Rogue_At_Heart's party entered the map on the east side, rather than the west. There is an exit point on the edge of the map very close to the Shade Lord, after all, and most maps have different "entry points," depending on where you just came from.
C) Resting in the Temple Ruins is enough to change the "Night" map into the "Day" one, thus making the path appear. This is highly doubtful, though.

But you need the Symbol to get through the door that's just south of the stairwell that connects the Temple to the Shadow Dragon's lair. Unless when you go downstairs you're set right beyond the door... Or perhaps Rogue killed the Shade Lord and the dragon, then turned around and went down the proper entrance?

And for the record, neither the wardstone nor the Symbol nor even the Shadow Jailer key vanish after the quest is finished. You get to keep them as mementos, gathering dust in a stronghold.

And just FYI, the Sun Gems do not disappear either--but only if you've got them in a container. Weird.