It kinda bugs me that some layout items steal some keyboard shortcuts, making them useless as global key bindings. For example, SongLists and SongTrees steal both space and ctrl-space, so they are useless as play/pause shortcuts. SongLists even steal ctrl-p, which I use for opening the Settings window.
My suggestion is that all key bindings are grabbed by gmb and checked against the keybindings list before the layout item in focus gets the chance to react to it. If the key or key combination is in the global keybindings list, it should not be passed on to the current layout item in focus. There should be one exception to this: key bindings that are plain letters or space (without ctrl or alt) should not be grabbed when a text field has focus (for example SimpleSearch or inline search in a SongList or SongTree). Typically, you want to be able to type a search string that includes a space, even if you have space as a play/pause shortcut key. This is the way itunes and spotify work and I find it intuitive.
My suggestion is that all key bindings are grabbed by gmb and checked against the keybindings list before the layout item in focus gets the chance to react to it. If the key or key combination is in the global keybindings list, it should not be passed on to the current layout item in focus. There should be one exception to this: key bindings that are plain letters or space (without ctrl or alt) should not be grabbed when a text field has focus (for example SimpleSearch or inline search in a SongList or SongTree). Typically, you want to be able to type a search string that includes a space, even if you have space as a play/pause shortcut key. This is the way itunes and spotify work and I find it intuitive.