[Clearly this whole quest with stabilizing the spell was how the spell-maker intended to quality control, Kaveh. Daqiang certainly wouldn't have crafted it in this manner.]

That is the how the spell was written. The one who casts it is to 'polymorph' the item it's cast on into whatever they want. It's sloppy, however. The spell-maker's desire is trapped inside the spellbase.

[He handed the scroll back, still dancing around the frog-sheep]

For some reason, the spell-maker wanted to see a sheep when they crafted the spell.