I want to make an attack for a unit that uses the Feedback graphics but is actually a weapon instead of a spell. How would I go about doing this? Or what would be the easiest way to do it?

To clarify, the unit in question uses the high templar graphics. Thus, the Feedback Launch actor would be somehow copied and used for the unit's attacking graphics. I'm kind of at a loss. =/

You'd need to define a weapon that calls Feedback (Set) as its effect and give it to the Templar. The Feedback (Launch) actor seems to be called whenever the Feedback damage effect is called, so I think that would be it. You may want to modify the Templar actor and display its feedback animation when it attacks.

Thanks, this helps. There are one or two difficulties, though. I also want to remove the energy dependency and just have the attack do a set amount of damage. Is there a way to do that?

Search for the "Feedback" effect, and look for "Cost" or "Modification" in the fields. From there, you should be able to remove energy dependency.
I'm too lazy to open the editor to precise a bit more. Sorry.

We really need a video tutorial posted somewhere around here on how to use actors/what they are for. You could just edit the feedback launch actor and add an event for your attack (assuming it is an ability). If it is an attack you should use it in your attack actor.