Well it turned out to be an Evocation spell, which is my oppositions school.
My first reaction was: "huh, that does not make sense."
I lost a 7th level spell pick - and its my fault for making an assumption.
But, I think that first reaction is still valid.
You summon the bow.
Then maybe you can argue that the bow, not its user, evokes the magic arrows. Or maybe even, the bow conjures the arrows. Regardless, it is the bow that does the creation of the damage causing magical missiles.
Once you summon the 'conjured' bow you then use it, without further use of magic. It is the bow that creates and the magical arrows, which are launched by operating the bow itself. The magical arrows are released from the bow only when the caster pulls the (conjured) string of said bow.
I have since realized I do not really need this spell after all. I thought it would go well with shapechange. Maybe it does..I am not sure but since it has been irritating me, I thought I would scratch that itch.