Mike, Kyrila,
My sister did locate photographs about the Douglas home, on Lake Minnetonka. It was a 27-room mansion, built in 1908-1910 on the site of the former Hotel St. Louis, and called "Walden" (the Douglas family must have been fond of Henry Thoreau!). It was filled with artwork, antiques and whatever, from all over the world. In 1927, President Coolidge considered staying there for the summer. My sister doesn't think it still exists, but a picture I have shows a what looks like a 1980 Mercedes Benz in front of the house--so it was at least around in 1980.
When Malaha and her maid went into the lifeboat, Walter told them "I'll see you in Cedar Rapids." Indeed, his body was recovered, and buried there.
Malaha smoked, used rouge, sometimes wore an Indian sari as a hostess gown.
Walter was a director of the First National Bank of Minneapolis.
Apparently, there was a book published by a Cedar Rapids author, which is believed to have been based on Malaha. It's titled: "The Tattooed Countess."
Email me your addresses and I'll send you this stuff.