Little Dragon,

You can just float them by dragging into the middle of the screen (where preview is) and reshape to vertical or horizontal or even 2 columns if you wanted to :)

The snapping feature is well implemented with docking windows.  Areas that you can dock into give off a glow effect.  Sometimes it takes a wee bit of fiddling.

No, the standard Library hide/show shortcut is Ctrl+Shift+B.  I have a Natural Multimedia keyboard and I can map certain keys to evoke macros when pressed.  I changed the "Search" key on my keyboard to do Ctrl+Shift+B, which effectively lets me "toggle" the Library.

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