You need fly on M&M integrated carriers (LH Group/OU/LO plus maybe LG) and access is only to own lounges. Example: WAW-FRA access to LO lounge (own lounge), BKK-FRA no lounge access as there is no LH lounge and other carriers treat you as *S and not *G.
Ahh, ok. Thanks. Their websie was a bit vague. They had star alliance lounges as accessible.