This is happening because open_basedir restriction is applied is your server, however I tried check it from plugin editor but edit is disabled or file is not writable in your site.
Certainly something is missing in your setup there, but it is hard to tell without checking, if possible give me wp-admin and google drive login in a private reply, I shall set it up there for you.
I just tested in your installation, order_by="download_count" is working fine, actually “order_field” and “order_by” both will work fine for that short-code.
This is actually totally depends on google viewer, wpdm have nothing to do with this though, I had to check the file to be confirm, however please give me the package url at least.
Don’t worry, we will add video play support soon, now wpdm already have youtube support, you can attach your tube url, template tag [youtube_thumb_0] will show youtube video thumbnail, [youtube_player] tag will embed youtube player in page for attached video url ( http://www.wpdownloadmanager.com/doc/templates/template-tags/ ).
that is not possible yet, but we are working on all in one short-code, where you will be able to build any custom query like that simple adding new short-code parameter, hopefully will be available with the next update of wpdm pro.
@therrmann, Sorry for issue, but trust we missed it accidentally, it is not like what you think. However we tested all fields with the add-on and everything is working there. Please update your copy.
