Problema con subir archivos. Upload file to Firebase

"Hola Anke, sorry for writing to you but I'm feeling a bit desperate now. I'm fairly new to App Inventor and programming, so I don't have much maste

ry of the subject. I'm trying to create an application to save (videos) files from the phone and store them to a Firebase storage database. I managed to save images using the image picker component, but I can't save videos using this process. I've seen that there's an extension to be able to save files from the phone. My problem is that I don't know how to do it with this extension, nor without it. I've also been trying it with the ActivityStarter. I'm attaching two photos so you can see what I'm trying to do.
"My idea for the app is that the user can choose a video from their gallery using the 'Add Boulder' button, play it on a video player, and then when they press the 'Save' button, it is saved to Firebase Storage."
I guess it will be very easy for you, but it's been a headache for me. Sorry for wasting your time. Regards."

Set the content type accordingly and show us a screenshot of your relevant blocks

Before taking the screenshot set the language to English...

See also How do you upload images from mobile to store in firebase dB? - #3 by TIMAI2


Other examples for uploading files to FirebaseDB.

Change file://mnt/sdcard..

and file:///android...