In the recipe for rolled buttercream, it says to use heavy mixer with a paddle. I don't have a paddle so do you think the dough hook would be ok?

You should be OK with the dough hook. You mainly want to get it all mixed together. You still will knead it on a work surface. I had problems with this tearing quite a bit when I tried to cover a cake. Let me know how yours comes out!

I've made one batch of rolled bc cause I've been looking for an alternative to fondant (nobody around here will order stuff like that, that they can't just cut & eat). I don't have a paddle either so I mixed it as much as I could with dough hooks, then kneaded it. I found I had to add quite a bit more powdered sugar than the recipe said...it may be higher humididity here. Anyway, I found it a little difficult to cover a cake with, and not great for molding or anything cause it doesn't dry fast or very firm. Hope you have better luck! It does taste good! I'm looking into MMF next cause everyone here seems to love it.