Were you able to get this to work? I had the same problem that in unreal the whole object rotates as a whole and not the individual cubes. I got to it work only when I made sure that the output node has name, N, uv, uv1 point attributes. But this replaced the vertex N attribute that I lost the real Normal values.
Actually just got it to work after exporting the pivotpainter node and not any nodes connected to it..