Rated 3 out of 5 stars

Are you on the problem that I already mentioned before?
-> https://addons.mozilla.org/en-US/firefox/addon/complete-youtube-saver/reviews/848178/

This review is for a previous version of the add-on (5.7.34). 

Rated 3 out of 5 stars

Before I use the addon to download a video from youtube the browser statusbar looks like this:
https://i.imgur.com/zPNJd81.png

As soon as I start downloading a video the statusbar looses some icons and looks like this:
https://i.imgur.com/aBOUszy.png

Also in some cases I still get 0 byte files.

This review is for a previous version of the add-on (5.7.34). 

We are looking into this...

Rated 4 out of 5 stars

When proceeding to the next video on youtube and then clicking on the button to download it, it gets the name of the previous video.
But I see this:
https://www.patreon.com/posts/testing-v5-7-32-8016764
and hope this is the issue you're talking about...

This review is for a previous version of the add-on (5.7.29). 

Yes, v5.7.32 fixes the file naming issues