This is definitely interesting to me because this is exactly why I got BIAB. I want to create backing tracks and as you have found you have to really manipulate to get the specific details of a song. I am not looking for note for note just reasonable. Real Band seems to work best for what I have tried so far. I am trying to establish a workflow that makes sense so I can whip these out in a reasonable amount of time then as we practice with them I can refine what doesn't work. I have tried importing midi versions of songs but that seems to be hit or miss with BIAB.