You must be looking at a way to display a meaningful name instead of the username? I wish they would get a decent security system, but doubt they ever will. It's not very elegant, but what I did was create an array of users in the plc. One member is username the other was a meaningful name for that user. I would display the meaningful name when the corresponding user was logged in. I had to create macros in login/logout to write the current user to the PLC.
Another option is just do all security in the plc. If you want it secure, so people can't see passwords, you could create an add-on instruction that's secure and use local tags, which can be used in ME as long as read/write privileges are set. But, unless you have the proper sk.dat you will not be able to see inside.
Just my two pennies.
James