Found a resolution. I only know some elementary stuff about ahk scripting, but I looked at the script I'd downloaded & noticed that in the "TRANSPHKEY" section the value of the hotkey that's been invoked is passed on to the transpnum variable, which is then used in the "TRANSPARENCY" section to calculate the transparency level. The hotkey, though, has the "!" character in it, but you only want the number that proceeds it. Searched through ahk documentation & found the command for extracting the character. Simply replace the line "transpnum:=A_ThisHotkey" w/ "StringRight transpnum,A_ThisHotkey,1" which tells it to assign the rightmost character in the hotkey to "transpnum".
Well, it's been educational talking to myself.