First, make sure that the shift key is unbound in the keybinding settings.
After that, if you’re using an auto fire software, you should only need to hold the shift key down when Demonbolt procs. I leave the Demonbolt spell on an action bar slot so i can easily see when it has procced (lights up with a flashing gold/yellow border by default). If you’re manually pressing an action bar slot that has the macro assigned, then you’ll need to hold shift and press that key to fire Demonbolt.
I hope that answered your question, was not entirely sure what you meant by “ahk settings”.
Prepared + Opportunity = Luck
"If you are prepared to take advantage of an opportunity when it arises, you will find that your luck with also rise."