Alright, I have a head built as a separate file from the body. I can smooth the UVs and unfold them in the original file, but once the head is imported into the body file the unfold no longer works.
Does anyone know why this is? Do I have a setting wrong? I can do the unfolding in the original file, but need to tweak it a bit when I reshape the neck to fit the various bodies that it will attach to.