Shapedata I've created gets changed when I move shape into a swimlane

[iand]

Hi,

I'm using the cross functional flowchart template.  I've created my own shape stencil with versions of basic flowchart shapes.

I've changed the shapedata on some shapes, e.g. the process shape, to what I want to store.

When I drag the process shape onto my drawing the shapedata is the list I expect.  If I move the process shape into a swimlane the shapedata gets changed to a default (I guess) and some of my fields are missing and others I don't want are there.

How can I stop this from happening and retain the shapedata I want?