- Maximize Window: F11 or Windows logo key + Up arrow
- Open Task View: Windows logo key + Tab
- Display and hide the desktop: Windows logo key + D
- Open the Quick Link menu: Windows logo key + X
- Lock your PC: Windows logo key + L
Since Windows logo key usage is not possible in key combinations it is not possible at all in Razer Synapse.
I know there is a submenu which allows the rebinds of windows functions but that's a but lackluster.