theres 2 files when you download the file at page 1 (very top page for idiots who didn't know).the file named ak2ifw_update_14_DSL.nds FOR the DSL. if you use ak2ifw_update_14_DSi.nds on the DSL, you got a 50% chance it works.
mine worked (phew!).
ak2ifw_update_14_DSi.nds = For a DSi that was...