[ul][li]The suggestions to add a "hideempty" parameter would only be useful if you have added drive buttons to your toolbars, which I don't think applies (judging from the default toolbars shown in the first post's screenshot).
If you want to make Opus show empty drives in the folder tree and/or when viewing the Computer folder, go to Settings -> Preferences and then type empty drive into the search field at the bottom left. It will then show the two pages with the options you want to toggle for the tree and Computer folder.
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[li]For the question about the Attributes column, please see the Folder Formats: Quick Guide for simple step-by-step instructions.
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[li]Please also ask one question per thread if you need any more help (unless the questions are closely related, of course).[/li][/ul]