Simlab Electronics Layer definition does not calculate any equivalent material property

Hello

In Simlab Electronics, when you have a complete PCB model , and want to use layer definition to create an equivalent layer, no material property in the orthotropic equivalent layer. Though I see the young modulus calculated for the Isotropic equivalent layer, PCBequivalent Meshlayer is created which I do not know what it is and some other. It is not really clear what each simplification is supposed to do and how it is different from the other one