I had the same problem after installing Lion. I could not preview Pro Res files.
I did find a solution I went to my programs drive > Library > Quicktime and (after coping the components to another hard drive ) deleted all of the components. I then restarted my computer and then I was able to view and watch Pro Res files in preview. I did have to install
http://support.apple.com/kb/DL1396 Pro Apps Quicktime Components after that to watch DVC PRO files.
I am still having one problem that is only half solved.
Quicktime 10.1 (Quicktime X) will let me export files if they are under 5 minutes with the 480/720/1080 options and I get the video and audio together, a nice H264 file. But if I try to open with Quicktime X a video longer than 5 min it will only export audio not matter if I try 480, 720, or 1080.
Anyone found a solution to the exporting problem?
(and yes I know that I can use Quicktime 7 as a workarond that is what I have been doing since upgrading to Lion)
Thanks in advance
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