Opus 10 Hide or show some folders in Folder Tree view

I have 3 related questions:

(1) How can I hide some folders like "Libraries" and "File Collection" is the display listing of Folder Tree in Opus 10?

(2) How can I show my Documents folder (My Documents) in Folder Tree?

(3) What is "File Collection"?

What I want to end up with is a Folder Tree that shows the following (In the order indicated):

Desktop
Documents (originally called My Documents)
Computer
FTP
Network (maybe, since I never use it)
Recycle Bin (maybe, since I never use it, but I can see it's value)

Thank you.

All the options that control what's shown in the tree are in Preferences / Folder Tree / Appearance.

File collections are like virtual folders, which you can use to gather real files or folders from different places in a new combination / place. They are no actual copies of the items, but more like links to them,
or shortcuts. For example, if you have several locations containing music, like C:\Music, D:\Internet\Soundclips & E:\Various Stuff\digitalized Vinyl, you can include them in just one single collection,
to have them handy. Also, your search runs can be included in a collection & saved (although there is too many ways of using it, like "saved queries", check the manual for this). Your default folder format for collections (under -> settings -> -> folders -> folder formats -> standard formats) will include the location column, to indicate the real location of files & folders in your collections.
You can also make subcollections, folders within the collections.

Note, that in the default settings you have to use Delete REMOVECOLLECTION to remove items from collections, otherwise they will be actually deleted. You can, however, make
commands to change that behavior, so that "del" will use Delete REMOVECOLLECTION, & a modifier key like shift is triggering an actual delete on the items (Delete REMOVECOLLECTION=auto SHIFT RECYCLE). The example uses the trash bin for deleting, except the items are too large for it. Basically the collections are very much like Windows´ libraries.

Thank you. Following my 2nd question above, I wonder whether I can list a particular folder (called 'Documents' and previously called 'my documents') in the top level of the Folder Tree, which is currently in my User Profile Folder. I use that folder all the time and would like to see it in the listing of the Folder Tree (also I'd like to see Downloads, which is also in my User Profile Folder). Is there a way to put those folders in the listing of the folders under Folder Tree. In other words, I'd like to see listed the following folders (ideally in the order shown):

Desktop
User Profile Folder
Documents
Downloads
FTP

Thank you.

If you look into your context menu of the tree item, you have the option "tree root here" (can be a bit different, as i use the german version. The raw command is "Set TREEROOT").
But this is only temporary. Also, no genuine arbitrary sorting is possible at the moment. If you would consider not to use the tree, but a collection including those locations, you could arrange
those folders using some trick; if you set descriptions for your entries (like running numbers 1 to 5), you could sort by the description field & achieve the arbitrary sorting this way.

You could have that collection as a default tab, to have those locations handy all the time. Or you could use the favorites system, which also allows you to arrange the items in any order.
One more way would be, for example, a toolbar, floating toolbar or autohiding toolbar containing those locations in that exact order.

Thank you. I'll try the Collection or Favorites options, as the other seems difficult to do for me.

You can try out the toolbars like follows: in -> settings -> customize you select the "toolbars" tab. Using Alt-N creates a new toolbar, which has to be named.
You can then, for example, check the "floating toolbar" option to create a new empty toolbar & drag into the size & form you prefer. In that you can right click & choose "new" / "new button",
which you can edit afterwards (also per right click), or, even much easier, just drag your desired folder right into it (still in customize mode). You can drag the locations in the desired order & click OK.
The toolbar is ready to use. You can also select vertical toolbars or autohide in the same menu. Of course you can also include all toolbars in your lister.

I created the floating tool bar and it works great. Many thanks!