Method script for add technical fields in PowerDesigner

I need to add technical fields to table in PDM, when I check one of Stereotypes in PowerDesigner. I imagine it should be a Method in Extension Properties for Table methaclass, but don't know how to bind event "Check Stereotype" with creating fields. I can't find similar questions here:( Сould you help with examples or links to similar topics?

If I understand your question correctly, you want to add new technical fields (I guess Extended Attributes) when you apply a Stereotype to an object (e.g. PDM Table).

You just add Extended Attributes under the Table stereotype in the Extension:

And they will appear in the Table property sheet, in the Extended Attributes tab:

You can then get a nicer display, by defining a custom form of type Property Tab, in the extension, under the same stereotype, to present properly your extended attributes.