... various other erros or just frieze up.
i seem to spend much of my time just trawling internet forums looking for an answer.
I have had my MacPro cylinder for 6-9 months. All of my Adobe products run superbly and are quite stable. I don't do 4k, it's unnecessary, but I do l;its of pre comps in 3k and 4k and pull them back into 1080 workspaces.
Your issues are probably not with the hardware or the MacOS. I suggest you start researching the sources of your 4k, how you get them transcoded, and how you expect to provide the output. To figure out if your 4k source material is part of the problem, try working in 740 using ProRes422 and see how your system performs.
The AE wonks will demand you post your system specs.
thannks for taking the time to answer.