Installation and server related problems

Dear Community,

I have created very large interactive books with numerous course presentations. I used the Lumi desktop software to create them. Yesterday I opened another student's course presentation with Lumi. 

Problem: now all (!) my own Course Presentations (inside all my interactive books) are no longer displayed. (Screenshot attached) I see nothing but white boxes. It seems to me that I have received a different/newer version of the course presentation?!

Hello. My Moodle installation has been giving me the following message lately, which appears to be from H5p "missing site uuid or hub secret. Please check your hub registration". Do you know how to delete that message?

Hi

I tried to use AR Scavenger on my Wordpress site. But I am getting an error that glb and gltf file types are not allowed.

So, I tried to whitelist these formats by editing the h5p.classes.php as suggested by Oliver here.

https://wordpress.org/support/topic/ar-scavenger-cannot-use-any-glb-gltf...

But when I try to save the changes, it is not happening. 

Please advise.