Enviromental Compliance 3.0 - Batch process step variable linking

Hi all,

I have been trying to create batch process recipe in Enviromental Compliance 3.0 SP15.

I have defined Input-Output Calculation, assigned it to a new Recipe and charged several materials, but can't link these materials to calculation variables - select button is just inactive. Though I can link parameters of materials, facilities and other. I did not find anything in EC functional documentation about this issue.

Is there any configuration that has to be done, in order to have this working properly?

Thank you!