Callouts lose association when the Callout layer is hidden
As the title describes, when adding a callout to a shape, and then hiding the Callout layer that is automatically created through the Layer Properties screen will break the relation between the shape and the callout. So when you make the Callout layer visible again, the callout won't be linked to the shape anymore.
The same behavior occors when you add the target shape to another layer and hide that one.
This doesn't seem very practical as it renders one of the Layer systems features, hiding certain shapes/information when you don't want to see them, essentially useless.
Wouter Roos commented
@David Parker: Thanks!, that seems to solve the issue.
David Parker commented
This can be solved with the addition of a reserved User-Defined Cell msvSDMembersOnHiddenLayer=1, see https://blog.bvisual.net/2018/10/24/fixing-the-layers-problem-with-callouts-in-visio/