It seems that opI.A and Adjoint[A].opI.A cannot be evaluated for spin-1 system in SpinDynamica 2.13.1 on Mathematica 9.0. My colleague has the same issue. He is running it on Mathematica 9.0 as well. Then we downloaded earlier version, SpinDynamica 2.9.1, and they are evaluated properly. I attached notebook to illustrate the error in SpinDynamica 2.13.1. Please take a look.