A MATLAB CAPE-OPEN Unit Operation must model a steady-state Unit Operation not a dynamic Unit Operation. COFE is a steady-state process simulator (like PRO/II, PROMAX, Aspen Plus) not a dynamic process simulator like Aspen Dynamics, gPROMS. That does not explain the issue you encounter but your objective won't be met. If you want to model a stand-alone dynamic CSTR in MATLAB, use the MATLAB Thermo Import to reach out for thermodynamic properties. But you should not have expectations to run this dynamic CSTR in a steady-state process simulator. The MATLAB CAPE-OPEN Unit Operation implements the CAPE-OPEN Unit Operation interface specification which is clearly mentioned for steady-state operation.

There is a CAPE-OPEN Dynamic Unit Operation interface specification. But it has been implemented only in INDISSPlus from CORYS. It has not been implemented in Aspen Dynamics or in gPROMS. The CAPE-OPEN Dynamic Unit Operation interface specification builds somehow upon the

CAPE-OPEN Unit Operation interface specification. But the additional interfaces to cope with dynamic operation are simply not there in the MATLAB CAPE-OPEN Unit Operation. I don't expect there will be there any time soon considering the small number of dynamic process simulators having implemented these.