The (third party) lounge at Bordeaux is not much to write home about. Nothing to eat, a couple of bottles of wine, and some quarter-bottles of gin, cognac and whisky. They sometimes have copies of the Daily Mail, but usually a few days old. Otherwise there is satellite TV and a departures screen. More often than not the lounge is unstaffed. Entry is by entering a code into a keypad.
The check-in staff are usually pretty clueless about who has lounge access, so try showing your Gold card and ask for a lounge access card (which has the entry code written on it).
The best aspects of Bordeaux airport are its small size (quick to get through security, baggage reclaim) and the free WiFi access.
Enjoy Bordeaux!