As stated here (http://www.escapefromunderdark.com/forums/showpost.php?p=183290&postcount=5) wall of fire should do a combust effect, from my understanding on casting 2d6 dmg and every round thereafter 2d6 dmg with a reflex save to stop it. I am not experiencing this in the game.
I don't think the extra combust effects from the perk or on this spell have a duration and thus, no reflex save.
Well- I'm not using the fire perk. What I was getting when casting the spell was the regular 4d6 fire damage. It didn't do any sort of combust effect or vfx.
This is fixed next update.