Do I have to run join.me as an administrator? (elevated privileges)
Some applications must be run as an administrator to properly function. join.me is not one of them. join.me works fine no matter what type of user account you use or how you run it.
That said, some users have reported issues when not running join.me as an administrator and attempting to share mouse control or share a window (see Trouble sharing mouse control? or Trouble sharing your screen or a window?).
If you experience problems, try running join.me with elevated privileges: right-click on the join.me icon and select Run as administrator.