Why do I always get warning pop-up after adding a shape?

[Chris G <cl isbd net>]

After I export a diagram as a .shape file and then add it into one of
my collections of shapes (using the Sheets and Objects window) then
whenever I open dia I get an warning pop-up box saying:-

    Several object-types were named diagrams - xw.
    Only first one will be used.
    Some things might not work as expected.

(of course the xw changes according to what I have called the shape)

Am I doing something wrong when I export the shape or is there something
wrong with dia's handling of shape export?

While I'm at it I have yet to be able to export a shape that actually
works as intended, the .png file doesn't show the shape properly and the
shape often seems to lose its colour properties and so on.  It all seems
a bit flakey.

-- 
Chris Green