Using MSX with Two Compartment Mixing in Tank

I am running an epanet model and using MSX to do some quality simulations. I recently realized that when I change the mixing model in the storage tanks from completely mixed to a 2 compartment mixed model, the water quality simulations in MSX do not work, and causes error 524- illegal math operation. However when I run the model with everything exactly the same, except for the tank as a completely mixed tank, the MSX model runs and does not encounter any error.

I was wondering if anyone else has experienced that, and if there is any confirmation that MSX requires the tanks to be completely mixed, and not use any of the other mixing models.