Gatwick
The Gatwick CRC Lounge is indeed available to all CRC members, although check the hours since they aren't typical domestic US CRC hours. It had a self-serve bar and had more snacks/appetizers than a domestic US CRC, as I recall.
The Arrivals lounge in LGW is NOT available to all CRC members. It is available to all DL BE travelers, and PM in Y, only.
I found this out traveling to Gatwick in Y in November, as a (then) GM, and was not allowed access to the Arrivals Lounge despite being a CRC member.
I informed Delta of the web site error by email back in November. They appreciated the email and error notification, but have yet to correct it.
Bob