Self Hosted Ubuntu Xenial 16.04 - Videos upload stuck in Queued (Flavors)

Hi!

I’m trying to install a Kaltura instance in my Ubuntu Xenial 16.04 Server.
I followed the procedure of your documentation: platform-install-packages/install-kaltura-xenial.md at Rigel-18.14.0 · kaltura/platform-install-packages · GitHub because it’s the only one I managed to follow and make it work.

After having modified many .sh files to make my Kaltura interface work, here I am facing a last (I hope) problem.
Everything is working (menus, image uploads, live stream) but the video upload is blocked at “Converting…”.
In the “Flavors” menu I can see “In Queue”. It only happens when I try to upload a video.

Here is what the kaltlog command returns to me at upload time:

I must admit that I have tried all the possibilities after having scanned the forum and other helpers in their entirety and I can’t find any topic on these errors precisely…

Thanks for your help!