UMLR — Activity Generalization is underspecified

Inheritance is specified as

When a Classifier is generalized, certain members of its generalizations are inherited

There is a derived attribute /inheritedMember, whose derivation is given in OCL, making it perfectly clear, what is inherited.
In Activities the inherited elements are defined only in the semantics paragraph:

A specialized Activity inherits the nodes and edges of its general Activities.

Since they are not members of the Activity, /inheritedMember will not contain them.

Suggestion
Add two derived attributes /inheritedNode and /inheritedEdge and specify the derivation.