Hi Coolscan & Co,
I have done some additional research and the combination of downloaded Cineform codec for QuickTime on Mac (the NeoPlayer for Mac, downloadable from Cineform web site) and Apples Compressor utility allow transcoding of 4K formats.
I tried ProRes 422HQ (3840 x 2160) , which turned 320 gb Cineform source to 280 gb mov file.
Playing this from MacBook Pro resulted in great image quality, but Mac could not keep up throughput and dropped sound. I tried to play with both QT and VLC, but both had problems with play back.
Now in process of transcoding to ProRes 422 and H.264 4k at 3840 x 2160 to see how these go.
The transcoding takes around 12 hours on 12 core Mac Pro, so testing different codecs is a slow process.