The Premium oneworld lounge opened in Feb 2011. Here are some pics from the MIA website:
It’s not the best lounge, but is only meant to be temporary until BA can get back into its own concourse which has a proper BA Galleries lounge with a First section and showers. However, as is the way with the mafia controlled MIA, it’s anyone’s guess when BA will be allowed back into its own space again.
I had soup and “champers” (Mumm Cordon Rouge) when I was last in there, but your description of it feeling as if it’s about to be repossessed is apt. Lovely ladies on the desk, though.