Custom Views vs. Custom Layouts
MB supports two levels of layout customization settings: custom views and custom layouts.
Custom view option shows up if you click on the view button ("Album" in the screenshot) and it only saves the layout of the main panel.
If you want to save the layout and settings of other elements/panels as well, you need to use "custom layouts" and it works per tab. Right click on the tab header ("Music" in the screenshot) and you will see the option. You can combine the two if you want to customize everything as a custom layout remembers which view is used in that layout. You can also pin your favorite tabs with a custom layout/view, not to repeat the setup process every time.