I need to create a PowerPoint presentation template that will be used in several different monitors/projectors. Are there any advices on how should I treat my template's graphics/design? Should I have two files? One for HD screens and other for low resolution ones?
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I would avoid saving 2 versions of the same file because then if there's any changes, you have to make them twice. Also, I design for the highest resolution (without making the files size too big) because it will look good on both HD and low res screens. You can take away pixels, but not add them back.
I agree with the link @e100 shared above to answer your other question on how to treat graphics within PowerPoint.