Unable to set up private shares

you would probably have to unmount and mount it again. It will also only show the shares available to the user/credentials you enter.

It will also depend how far in you went with the path:

//192.168.1.50/Public vs //192.168.1.50/

http://osxdaily.com/2010/09/20/map-a-network-drive-on-a-mac/