Video formats

The final thing that made it work was realising that not all video formats are accepted by the free version. It will happily import them, but they can not be dragged on to the time line. Or if you succeed in creating a new timeline with them on, nothing is played as the play head traverses through them. This ffmpeg script seems to work to convert files:

ffmpeg -i infile.mp4 -vcodec mjpeg -q:v 2 -acodec pcm_s16be -q:a 0 -f mov outfile.mov

Described here: https://www.reddit.com/r/davinciresolve/comments/pxicvk/comment/ho2inmz/ , In fact there is listed a batch command:

mkdir transcoded; for i in *.mp4; do ffmpeg -i "$i" -vcodec mjpeg -q:v 2 -acodec pcm_s16be -q:a 0 -f mov "transcoded/${i%.*}.mov"; done

Video card always on

It seems you need an external video card to run Resolve too, and the card must be active when running the installation script. Or you will get missing license key once you run the application with the graphics card.

Not that there comes any license key with the free version.

In order to switch to the card being always on I used the nvidia-settings app. I tried to do it also with some CLI command but it did not seem to stick.