I'll answer the second one:

At First you create 3 or 4 Pages in your "elder" - event. In the first one you write the eventcommands for your first meeting with him.
When you created the "show choice" and you have got the two options "I want to do the Quest" and I don't want to then you create a "change Switch" command in the "Yes (I want to...)" case and set any switch you want (not an allready used one) to "on". It'll be the best if you call it "Elder Quest yes" or anything that you can recognize later. In the "No (I don't want to...)" case, you create another "change switch" in which you set another Switch called "Elder Quest no" to on.
Now you select one of the other pages in this Event and set a tick next to "Event Condition" > "Switch" and select the switch "Elder Quest no". On this Page you can write what the elder says if you didn't want to do the quest.
Now you choose the next Page and select the switch "Elder quest yes" as event condition. Now you write what the elder says if you have chosen to do the quest but have not yet finished it.
In the Cave or dungeon where the searched item is, you create a new event representing the Item. Here you also create three pages. the first completely empty (even the graphic)
On the second page you select a fitting graphic for the searched Item and set its event condition switch to "elder quest yes" and as event start condition you select "push key" On this Page you show a Message like "I got the right Item" or anything you want to. Important is just that you make an "add item" command at the end which places the Item in the Inventory of the Hero. And finaly you change another switch ("Elder quest done") to "on" and set "Elder quest yes" to "off".
In the third page of the Item you select an empty graphic and as event condition you select the switch "Elder quest done"
Now return to your elder event.
Here you just select the last empty page of it and set the event condition to switch "Elder quest done". Here you finaly write what the elder says, when you return with the needed item.

I hope this helped you.

*edit* Mist zu spät