@davidh2k the problem is if we set up privileges for some users for public (say RW) and also with guest allowance, smb.conf output's this valid users directive, which will prompt for login. I am currently working on something around this with the extra options.
I manage to get this working with user/pass logging guest/[blank password]
If I understand he wants a folder to be read only with no login prompt, and for some users to have readwrite when they use their credentials.