Can you flame a flame that's on something, requiring you to disenchant the first, then the second, to get the item?

How do you disenchant items? Time/mana requirements?

Is disenchanting based on the skill level of the person that made it, like dispelling illusions from a low/high skill level illusionist?

Instant. 2 power. No level involved, anyone can disenchant any sigil, providing they can make it. Not sure on mana costs. You can't attach flames to flames, and you can't burn flames on other sigils. Burning a sigil with a flame will get you only the sigil, not the flame.

(I think)

So, if I went around dropping stuff all over the world, it'd be fairly easy to unflame and take everything?

Not that I would...

I'm not certain if you can unflame flames on items. You'd have to get an enchanter for that. I just know you can't unflame other sigils. You can only destroy the sigil.

For example, leaving items flamed across the land. An enchanter could just come by and have a field day, no?

Once the flame sigil is attached to another item, it can not be disenchanted. I've tried it before on a piece of gear of mine and I was not allowed to target the sigil. Once attached, it is like it does not exist anymore.

Good, good. Then I shall start leaving things in places they should not be.

I once proposed a propaganda assault on Magnagora in my Order where we'd leave preserved, flamed letters all of Magnagora trying to convince people to redeem themselves... I figured I'd get in trouble for it though (since after I spent 15,000 gold to flame/mono all of Capricorn, enchanters could disenchant the next day)... and I like saving the idea for a rainy day.