Export selected images in Aperture to desktop folder?

Very, very new scripter, so please be patient! My aim seems to be very simple: to export selected images in Aperture to a designated folder on my desktop, but I am unable to work out how to do it. I have searched the forums and all the scripts I have found are doing all kinds of additional things that I do not want to do and I have got lost and very confused, (trying to run before I can walk I think).

So can some kind person please, in very basic language, point me in the right direction? Many thanks for you help and patience.

Andrew

This should get you started:

set exportFolder to (choose folder with prompt "Choose an export folder")

tell application "Aperture"
	set imageSel to (get selection)
	if imageSel is {} then
		error "Please select an image."
	else
		export imageSel naming folders with folder naming policy ¬
			"Project Name" using export setting "JPEG - Original Size" to exportFolder metadata embedded
	end if
end tell