Change the background shape of master slide in PowerPoint?

Do you mean you don't know how to get into the master slide to change an image/ shape in the background or you want to change the actual slide size??

In Powerpoint 2007/2010:

To change the master slide go to view - slide master and you should be able to change anything there.

If you want to change the slide size in slide master view (as above) go to page set up. Alternatively you can access it through Design - page setup. You can create a custom size if needed.

Sorry if I'm on the wrong track completely, not quite sure what you're asking.

Thanks for your answer, Kat. I probably didn't explain it correctly.

I understand the capabilities of the Master Slide View (changing size, look, etc.), but I want to change the actual shape of the background. Please see the atachment. I'd like to change the shape of the blue background to a soft-edged rectangle (similar to the shape where the text/graphics are. Does that make sense?

I'm thinking I need to change it in Player Templates, but I don't see an option for changing the actual shape of the slide background.

Any help is greatly appreciated!!

Just found this conversation in the forum about slide sizes, doesn't specify shape but might rule out what you're trying to do???

http://community.articulate.com/forums/t/2047.aspx

You can definitely get this effect using a custom skin

here is one I did for another project http://moodle.mylearningspace.me.uk/file.php/1/elearning_for_approval/Test/player.html

Phil