tkle, you are better off posting this in the Lua/XML help thread in the Developer section of the forums.
Not really to your point, but line 9 contains superfluous code.
Lua Code:
if not SUIDB.A_ITEMLEVEL == true then return end
-- is exactly the same as writing
if not SUIDB.A_ITEMLEVEL then return end
not assumes false or nil values. It does not distinguish between false or nil, so if you are checking against true, false, and nil, then you'd have to specify.
Conversely, these are the same:
Lua Code:
if something then -- assumes true OR a value that is non-nil and non-false, like 1 or "dog"
if something == true then -- also non-false, non-nil, but specifically Boolean