Unable to record movies using motion

Hi
I try using motion to record movies from two monitoring webcam running 23.05.2 and motion 4.5 from the distribution.
webcams are connected to APs running mjpg-streamer. The video stream is OK from a remote connection.
Using motion webcontrol interface the two cameras are accessible with no problem in control pannel.
When a motion event occurs pictures are recorded with no problem but movies fail

the relevant message is as follow

event_ffmpeg_newfile: Error opening context for movie output

this is consistant with the log message during the init phase of motion

ffmpeg_global_init: No ffmpeg functionality included

Looks simple, ffmpeg is missing! But loading ffmpeg package doesnt' change anything

looking at this post: https://forum.openwrt.org/t/motion-on-19-07-ffmpeg-global-deinit-no-ffmpeg-functionality-included/100483/4
It was said that the buid shall include build_patented
Allright, I build the FW for my target. I have included le motion package (streaming->motion) and I have enabled the appropriate build option (global build settings->Compile with support for patented functionality)

And.... it still doesn't work, same error messages meaning the ffmeg functionality is not linked to motion (ffmepeg package installed or not)

I probably missed something. Does anybody know what to do?

Hey, how did you solved the problem?

I have the same errors in the logs and it isnt recording videos.

sorry, not solved yet