Thanks for your prompt reply, Eric!

I had made screenshots previously, but then I noticed that I get the copyright notice, when doing a copy/paste and wanted to include this. But my images can't be fully embedded, they are not editable when double-clicking (as mentioned in that article about Word). PowerPoint treats them as graphic (like any bitmap image) when I double-click on them.

Anyway, I found a workaround meanwhile: I right-click on the image in PowerPoint, choose "Save as graphics ..." (is that the right English term?) and save it as a JPG- or PNG-file. Then I delete the one coming directly from MapPoint and insert the new one. One more step to take, but it works!

Kind regards,
Ute