I used to use your product with fine results. I upgraded to the pay version and can not download any video I have it turned on and I am on the default setting. I open a video and nothing happens. Please help
I would start by suggesting you do a basic reinstall - uninstall (delete from Application), reboot, reinstall.
If the problem continues can you confirm that the download fails even with a basic YouTube video? That is usually a good baseline test to determine if there is an issue.