Sooo… I’ve read everything I could about this topic and my impression is this:
AHK is talked about by GMs and support as a grey area, but you are more likely to be banned even if you make keyboard macros just for “One action per keypress” rule, so it’s not worth using.
Mouse and keyboard software is kind of a lighter grey area, because it’s harder to prove that you are not just a pleb that only knows he instaled some software and it keeps switching on every time he boots up.
I guess my question is to get an idea about how much I can take advantage of various 3rd party software for customising my keybinds. For example on an ahk script:
$4::
Send 46
return
… makes my button 4 cast 4 and 6 at the same time. 4 is a Fear on warlock and 6 is his Curse of Exhaustion. You have to cast Fear while standing and it’s before 6, so it will always cast only fear while stationary. But if you are moving it will cast Curse of Exhaustion .
Is that fine with the ‘One action per keypress’ rule? Or completely diabolic terrorist, puppy-killing faux pas, that gets me banned for the rest of my life? If it’s a grey area, is it a coin-flip if I get banned just because I had ahk active?
I need answers 
… I love customising my UI, but I don’t want to be banned.