How to make selections in Impress

[mneumann@sta.at]

I am trying a fairly simple task of replacing an existing graphic by a new one. I was sucessful doing that with the graphicURL property of the Shape object, just that the result was a linked graphic. In order to get an embedded graphic I tried to make a selection of the existing graphic and then simply insert a new graphic, which is going to replace the selected one. I could figure out the insert part but was not sucessful yet on making the selection. Anybody has a hint for me how to do that?