can anyone help, please, with this Address Book plug in?

Here’s what we’re looking at: I’ve hacked a couple of scripts together, hoping to be able to “schedule call” of a selected phone number in Address Book. The “schedule call” was the original script, but the part I hacked in is that it presents me with a dialog to choose which calendar in iCal it should schedule the number in. I get the dialog properly, choose the calendar I desire, but then the ‘script stops. I’ve tried just about everything I can think of, but still at a loss. Both parts of this script that I’ve “frankensteined” are others’ work, so if it looks familiar, that’s why.
Can you tell me where I’m going wrong here? BTW, I think the address book plug-ins only work with 10.3, but I’m not positive on that.
Thanks much, in advance.

property cal_name : “”

using terms from application “Address Book”
on action property
return “phone”
end action property

on action title for p with e
	set theName to (first name of p)
	return "Schedule call to " & theName
end action title

on should enable action for p with e
	return true
end should enable action

on perform action for p with e
	if cal_name is "" then
		if check_for_cal(label of e, true) then
			set cal_name to label of e
			choose from list (get_cal_names()) with prompt "Schedule in which calendar?" default items {"Home"}
			-- choose whatever dialog to display between the quotes
			set cal_name to item 1 of the result
		end if
	end if
end perform action

end using terms from
– from Address Book

– now we’ll call iCal
using terms from application “iCal”
on check_for_cal(cal_name, needs_write_access)
tell application “iCal”
repeat with c in every calendar
if (title of c is cal_name) then
if needs_write_access then return (writable of c)
– or if only needs existence
return true
end if
end repeat
– if no calendar matches the desired calendar name, return false
return false
end tell
– application iCal
end check_for_cal

on get_cal_names()
	tell application "iCal"
		return (title of every calendar whose writable is true)
	end tell
end get_cal_names
-- the above is telling iCal which to display in the picker box

on add_item_to_ical(id, name, cal_name, cal, c)
	tell application "iCal"
		repeat with c in every calendar
			if title of c is cal_name then set cal to c
		end repeat
		set theItem to (make new todo at end of cal)
		set summary of theItem to "Call " & name
		set url of theItem to "addressbook://" & id
		show theItem
	end tell
end add_item_to_ical

end using terms from
– from iCal