GOTCHA: MagicDraw/Cameo: SysMLv1/UML: The argument context required to see results in Evaluation Mode for custom OpaqueBehavior scripts might not be the same as required for use in an Operation From Model for a Derived Property on a table column
In some cases the context of an argument required to test an OpaqueBehavior in Evaluation Mode needs to NOT be the THIS that is used to feed it when re-used as an Operation From Model in the Expression Editor for a Derived Property or Custom Column.