Absolutely! As long as we're talking static Lower 3rds, then yes, you can load a PNG with alpha in to a Media Store and then use that for any type of keying need. Lower 3rds, Location bugs, additional info for the topic at hand, whatever.
I create the PNGs in PhotoShop simply as a image with transparency. No need to add additional specific channels for the Alpha channel.
The only thing to remember: Carbonite wants the resolution of your graphic to exactly match your system resolution.
1080, P or I? 1920 x 1080. Not 1081, not 1919, but exactly 1920 x 1080.
Same for 4K if that's your world, 3840 x 2160 not something else.
Good luck!
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Kevin Lawson
Senior Engineer
Ice 9 Productions
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