I'll try to get a video up about it. It's actually easy to use if you know how to.
I don't know why none of the other buttons wouldn't work for you. It seems to work on the page for me. And I just downloaded to app and tested to make sure the file wasn't broken. I'm not sure why it won't work for you
I just tested it on mobile too, and it seems to work too. Try downloading it and running it local.
The video is up if you want to watch it (It's right her in the page). I hope it helps!