Thanks for contacting us here about this extension.
we selected file to download and get an warning message 'xxx.zip file is not commonly downloaded and may be dangerous' with a button 'Discard' , can this message be removed
This message is not from our plugin. It could come from some reasons: your files are containing virus or your ip address is blacklisted.
Normally, this message is not appeared on our test site. For example: https://www.joomunited.com/wordpress-demo/wp-file-download-default-theme/
If your purchased, please drop us a ticket (menu Support > Ticket support). Our developer in charge will take a look at that.