Does windows 10 second preview release have the ability to PIN the windows to the desk top???
1. By " second preview release " I assume you meant build 9860.
2. I am assuming again. By "Pin the windows to the desktop", you meant you want to see Start Menu in desktop instead of Start Screen when you open your Windows computer.
If yes, the only way is to.........
right click at the taskbar > select Properties > click Start Menu tab at top > check the box "Use the Start menu instead of the Start screen" > click Apply/OK > you will be asked to restart to complete the setting change. Do so. > after restart you will be opening Windows in desktop every time.
If you want to undo the change, repeat the steps above and UN-check the box instead.