There is a variable near the bottom of every skill. It contains a list of character strings (words). They may have things like Ground, Air, Ward (kinda like Targets Allowed on the attacks). You must add Enemy to this list. Double click on it, and check enemy.
If you want to do things like make an armor drop aura. Then take Devotion, set the target to Enemy only and make the defense bonus -. The %Drop must be FALSE.
But if you want to do things like a DPS aura. Then you need to edit the passive immolation damage and range. But not if you want it to channel, then either modify Starfall or do the above to Tranquility
I can't really give a step by step method because I am not running WE atm.
But look for it, and you will find it.