No, if you're using ISBoxer there is NO reason to do it like this. Simply create a keymap with a Send Next Click funtion and send the key that is bound for the AoE spell. Export to IS, go hit the button for the AoE spell, then click on the main's screen, and the slave will click in the same location. It's relative to the click on the main, so if they're not facing the same way, make sure you account for this.
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