Looks like I wasn't the only one interested in working on this. DisabledMonkey, dword and uint64 aren't the same size (the first is 32-bit, the 2nd is 64-bit). Now, on to the changes I did, because this project shouldn't die! (from the top of Midiudf.au3):   ; *Altered by GMK -> cleanup of code, Constants 'cleanup', addition of Drum Map ; *Alterations by Ascend4nt: ; - Changed '_NOTEON/OFF' to _ON or _OFF per suggestion by Paulie ; - @error checks/returns fixed (still some consistency