I put a shortcut to the "Computer" folder on the panel in LM14 Cinnamon this way:
Right-click an existing icon on panel, eg. Firefox
Click "Add" - "Add panel launcher" box opens
Fill in the fields:
Application: nemo computer:///
Icon: click on folder icon next to empty field to navigate to your desired icon, then click "Open"
(Instead of navigating to the icon, I just typed this in the icon field - for the default Mint-X icon):/usr/share/icons/Mint-X/devices/22/computer.svg
Then click "Add"
Edit: Discovered a much easier way than the above after posting
Menu > Accessories > right-click "Computer", click "Add to panel"
Note that when you do it this way, the command is gnome-open computer:///
instead of nemo computer:///
Anyway - now you have two ways to do it