Yes, it is a problem with the battle script I'm using, Solar. Unfortunately, I am no programmer, so the only way around this niggling little bug would be to "think before you act". I.o.w, do you really want Alys to attack all enemies, or do you want her to buff or cast a Tech? It's what I normally do. It's possibly the simplest solution I have right now.
And Xan, you said you were getting floored by Zio. What levels are your characters? Maybe you have the wrong armour equipped, because like I said in the very first post of the main BaNL thread, the right armour can mean life or death for your characters. Especially when going up against Zio. In this case, you need to equip Alys with both the Platinum Shield and Platinum Armour. It greatly reduces elemental damage, since out of all 5 characters in your party against Zio, Alys is the most vulnerable against Zio's Black Wave and Corrosion attacks. So is Gryz, but he's expendable. Cold, I know, but I purposefully made that battle one where you have to make sacrifices and consider which ally is your most valuable. In this case, try to keep Demi and Rune alive as well, along with Al.