We have a Powerpoint .ppt file that contains WordArt. The file displays fine in
Impress as a ppt file. When the file is saved to .odp, the WordArt is still
visible until you close the file or the application and then re-open the odp.
When you the application is closed and the .odp file is opened again, the
WordArt is gone and the a diagonal line is left in it's place.

Looking at the content.xml file from within the odp file, it seems that the
wording of the WordArt is making it through ok and if you double-click the line
in Impress, the lettering appears behind it (though not displayed as
WordArt/fontwork).

Powerpoint 2003 and 2007 are of course able to able to open and display the ppt
file correctly. If you then save the problem file as a new ppt from within
Powerpoint, open with Impress and then save as odp, the issue does not occur if
the file was originally saved from Powerpoint 2007, but does occur if the file
was saved as ppt by Powerpoint 2003. I don't have any other Office versions to
test with.

I have not been able to create a file from scratch in Powerpoint which
replicates the issue, but I have been able to copy only the problem WordArt
element into a new ppt file and the problem is repoducible using this file. I
will attach is and some screenshots shortly.