Originally Posted by keeton
If you are a SkyTeam ElitePlus (which includes Platinum Medallion on Delta), then you have access to international lounges regardless of class of service. Ironically, a Platinum cannot use a BE lounge for domestic travel.
IIRC, even PMs and other SkyTeam Elite Plus members cannot use the BE lounge on an international itin unless traveling in BE or business class on another SkyTeam carrier. An exception is the lounge in Terminal 2 at JFK which serves as a combo BE/CRC lounge.
As far as access to the LGW Arrivals Lounge at the Sofitel is concerned, I would print out the "CRC locations" section from the DL website which seems to indicate access to the lounge based on CRC membership.