Messages in collaboration diagrams

[Ed]

Hi,

is there any way to show messages (seem to also sometimes be called collaborations, e.g. right-click "collaboration properties" brings up a window with the title "message properties"!) in a collaboration diagram other than by creating new ones?

Two scenarios:

1 - a message is set to invisible in the diagram in which it was created. How can this message then be shown again in this diagram?

2 - a message is created in one diagram and should also be shown in a second diagram (e.g. to split a collaboration sequence across multiple diagrams for clarity)

Surely the messages should also appear somewhere in the project browser too?

Thanks in advance!