Genetik57 I updated to the latest 5.11 version and tried the steps above. First time lines of code appeared and it really look like it have work. I then restarted my laptop and no video appeared.
I tried it again and got this error
/recalbox$ PATH=$PATH:/usr/sbin /recalbox/scripts/recalbox-save-overlay.sh
Making /boot writable...
Mounting the overlay file...
Saving the real overlay to disk...
sending incremental file list
recalbox/system/resources/splash/
recalbox/system/resources/splash/recalboxintro.mp4
var/run/utmp
rsync: write failed on "/overlay/saved/recalbox/system/resources/splash/recalboxintro.mp4": No space left on device (28)
rsync error: error in file IO (code 11) at receiver.c(393) [receiver=3.1.2]
It looks like there's no disk space left? I have several gigabytes left on my hd...