I took a look inside the file ‘wpdm-box-com/wpdm-box-com.php‘ and I noted that there is quite a bit of the code commented out preventing any config on the settings page. I think you have the wrong package uploaded to your website.
Line 22 – remove comment
Line 51 – remove comment
Line 56 – remove comment
Line 60 should be edited to read ‘?page=wpdm-box-com
I’ve corrected all the above and it now appears to work though I haven’t really gone too far into the options yet.
Attached is the corrected php file version 1.1.0 in case anyone wants to review it.