You are not able to sort by Filename in the Marquee browser. Despite choosing to sort by Filename, the files are neither sorted in ascending nor descending order of file name.
The Support team isolated this behavior to a defect (Xinet-9602) in an older release of Xinet. The Development Team fixed this in the 2020.1.1 release of Xinet.
To resolve this issue, upgrade to Xinet 2020.1.1 or later versions by visiting the reseller portal and navigating to Downloads > Released Software > Xinet > Xinent 2020.1.1(or later versions).
Supporting Article: Downloading Xinet Installers
Confirm that you are now able to sort by Filename in Marquee.