I'm trying to get to grips with the rules for lounge access for our (free!) Lounge directory.

When I use the Star Alliance lounge finder (which maybe is a source of 'nearly' truth) it returns a bunch of lounges and many of them have Airlines associated with them. There is also the concept of a 'contract' lounge. From a *rules* perspective is my understanding of the general tenet to be:

If it's a Star Alliance airline owned lounge (eg LH, AC, AI etc) then Star Alliance Gold status gets access - period. Business and First travellers on that airline also get access. Business and First travellers on other Star Alliance airlines I am not 100% sure about.

If it's a contract lounge, then travellers on the contracted Airline are allowed access but there may be specific rules associated with it. In general it may be that Star Gold and Business/First get access but in airports (like JFK) where an alternate lounge is available access may be reserved for travellers flying Business and/or First with the Star contracted airline but Star Gold use the Star Alliance airlines' lounge(s).

I'm sure it's a bit more complicated than that - can someone enlighten me ?!