UML24 — is composite, but does not subset ownedElement

I tried to collect critical metamodel implementation issues we have in our tool.

Critical means that every time we must do changes in metamodel to be able to implement it.

I believe, Eclipse UML2 implementation has exactly same issues.

Issues may be devided into such groups:

1. Properties which are composite, but do not subset ownedElement. Our solution - subset ownedElement

2. Properties which are composite and subset other composite non-derived property. Our solution - make it non-composite as element can't be owned in two places

I'm not sure all issues are reported, could someone help me manage that and check if all these are really must-be-fixed bugs?

Most of these issues may be verified by running automatic script on metamodel file.

See details below:

1) is composite, but does not subset ownedElement

Duration::expr:ValueSpecification [0..] is composite, but not ownedElement
LinkEndData::qualifier:QualifierValue [0..*] is composite, but not ownedElement
LinkAction::endData:LinkEndData [2..*] is composite, but not ownedElement
TimeExpression::expr:ValueSpecification [0..] is composite, but not ownedElement
ValuePin::value:ValueSpecification [1] is composite, but not ownedElement
State::deferrableTrigger:Trigger [0..*] is composite, but not ownedElement
CreateLinkAction::endData:LinkEndCreationData [2..*] is composite, but not ownedElement
StructuredActivityNode::edge:ActivityEdge [0..*] is composite, but not ownedElement
ValueSpecificationAction::value:ValueSpecification [1] is composite, but not ownedElement
AcceptEventAction::trigger:Trigger [1] is composite, but not ownedElement
DestroyLinkAction::endData:LinkEndDestructionData [2..*] is composite, but not ownedElement
Stereotype::icon:Image [0..*] is composite, but not ownedElement
TimeEvent::when:TimeExpression [1] is composite, but not ownedElement
InteractionUse::argument:Action [0..*] is composite, but not ownedElement
SequenceNode::executableNode:ExecutableNode [0..*] is composite, but not ownedElement
Transition::trigger:Trigger [0..*] is composite, but not ownedElement
StructuredActivityNode::node:ActivityNode [0..*] is composite, but not ownedElement

This issue affects the Model Interchange Working Group (MIWG).
Issue 1 is accepted: All properties which are composite, are made to subset ownedElement.
Issue 2 is not accepted. It is acceptable for a composition to subset another composition. This does not lead to an element being owned in two places; it leads to an element being owned in one place by two links.