Installation issues on Linux Mint
I've decided to try installing Linux Mint to see how Cinelerra performs.
Following instructions from the Download page allows me to install from the repository, but I can't launch Cinelerra because it reports missing libpng12. I found this and installed it manually (it's not available in the repositories), and then ran into a missing libva. I haven't found a .deb to resolve this issue, so at this point I gave up and installed a single-user static build, which works fine (but doesn't seem like an ideal long-term solution).
I think it would be worth updating to the latest version of Mint on your build system (I presume building based on outdated libraries is what's creating these problems). Incidentally, Cinelerra seems to perform MUCH better on this OS than AVLinux. I will try to get some objective results to share.
As you suggested we did a fresh install of Mint 19.3 here. When we attempted to do a package install of CinGG from the 01/31/2020 package Cin was not able to start due to missing libIlmThread-2.2.so.12 and libIex-2.2.so.12. This confirms what MatN already verified but does not match exactly the problem you reported of wrong libva..., etc. Anyway we build 19.3, build CinGG, and Cinelerra ran without problems so we will use this for the monthly builds. There is a test package build at:
if anyone wants to try it before March 1.