Hi Sean: Sorry to hear you're having a problem playing ProRes Quicktime files. Usually it's pretty straight-forward.
It's either some sort of software configuration/installation issue on your computer, or your BMCC ProRes QT files are somehow corrupt/damaged and thus unplayable.
If you have access to another computer (Windows or Mac) with Quicktime installed, try to play these same QT ProRes files on that machine. If the ProRes files play fine on the 2nd computer, then that's good news: Your video is OK. If they don't play, that's not good news. If possible try them on a 3rd computer. If still no joy, then it would appear your ProRes files are no good (damaged/corrupt). You'll have to troubleshoot further to determine why & how the files became corrupted.
Assuming your ProRes files play OK on other machines, then you'll need to troubleshoot the software config/install on your 1st machine. I can't offer much help with that other than to suggest contacting Adobe and asking them what they recommend as a configuration & installation to support ProRes Quicktime files using their software. Adobe tech support (and perhaps other users in Adobe's online support forums) would be the experts on that.
Let us know what you find out.
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