you can set up multiple users by selecting Admins and adding your user accounts. You can then set them to Read access.
As for the Winbox with username and password, it may be possible, but I haven't been using the duds long enough to figure that part out. It looks like you can create a tool, and there are variables for username and password available. But it looks to me that you would need to write a function or other method to connect and then prompt for that un and pw.
I can't be a lot of help with this part, as I don't have any ROS devices connected right now to play with
"Technology is dominated by two types of people: those who understand what they do not manage, and those who manage what they do not understand." - Putt's Law