If you just want a group of users to be able to share a directory do the following:
- Create a group, and set a share directory for it. For example group name: mygroup, share name: mygroup
- Add as many users as you need to that group
- Save changes
To access from a windows machine you could you the explorer to point it at:
\\ebox-ip\mygroup
Then you will be prompted a user and password.