A professional diagramming tool that helps users visualize complex information through easy-to-understand diagrams.
Dear Tractor7955,
Thanks for posting in Microsoft community.
May I confirm if you are using the Backgrounds feature like below?
You can use this feature to change the background color.
For your second question, you can hold the left button of your mouse and select the whole diagram, with the circle on the corners, you can change the sizes of the diagram.
If the scenario above doesn't consistent with yours, feel free to point out and I'll help you figure out.
Thanks for you cooperation, look forward to your reply.
Sincerely,
Sean Cai | Microsoft Community Moderator
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