Never, ever give someone admin access to your installation. We are all nice guys, but you never know who is also reading and having access to your installation allows to change passwords and lock you out of the installation.
So give us a test link to a survey, but never give someone access to the admin interface.
I answer at the LimeSurvey forum in my spare time, I'm not a LimeSurvey GmbH employee.
No support via private message.