NOTE: If panels are Locked they will not be movable, Right-Click on the panel dock OR use the Menu > View > Toolbars and de-select 'Lock' if this is the case. To see how to edit the Toolbar click here. Dragging content over the main window buttons (Playlist, Channel Rack, Piano roll) will bring these windows to the front if they are not already visible. NOTES: Click on the above image for help on that panel.
Many of these commands are also available, contextually, in FL Studio menus and windows. FL Studio Toolbar, by default, is located at the top of the screen and provides quick access to many commands and options.