Well I just went to the lounge to see what would happen after the lady at the check in desk informed me that I wouldn't be able to get in. I gave my boarding pass and *A Gold card to the receptionist and the let me straight in, no problems at all.

Rest assured I will be contacting Star Alliance about this. The woman at the check in desk was clearly lying to me! She even "phoned" the lounge to ask if I could get in. Shame I didn't get her name!