The new adventure begins!
Noxias, Shock Sphere is one of my favorite spells as well with the other wizards I play.
Regarding marching order: I think we discussed Rogur taking point, with Konstanz at the rear. However, that was before I realized Zephyr would be accompanying us on this leg of the journey. With that in mind, I think Zephyr would be point and Rogur second, either side-by-side or immediately behind. Squishies in the middle, and Konstanz toward the back.
I don't know that Konstanz is any more fortitudinous than our other spellcasters, though, so if she'd prefer to remain in the middle, then just speak up, cutopia. Rogur will drop to rear guard and use his sling for ranged attacks.
Rogur is mostly useless for Nature checks (+2), but he's got a decent perception (+9), so he will help locate water. I think Yrisz has the highest perception in the party, though, so rather than make a primary check, he'll aid Yrisz' perception check for el agua.
If Ithelryn elects not to have Yrisz make the primary check, Umiushi, please roll for me and have Rogur make the check.
* Rogur - Perception - Aid Yrisz' Perception check to find water *