Adolf Rosenberger, also known as Alan Arthur Robert

Can anyone help me with information about this 1920s automobile race driver and Businessman who partnered with Ferdinand Porsche when Porsche's Design firm was established in 1931?

Here is what we know:
1. He was Jewish, and would be in a concentration camp for some time before going to France, Britain and finally the U.S.
2. During the 1920s he was a driver of distinction; According to Richard von Frankenberg he raced Mercedes cars between 1925 and 1928, finished 2nd in the 1929 German Grand Prix in a SSK, 2nd in the opening race at the Nurburgring in 1927 in an S, and bested Caracciola at the Freiburg Hill-Climb in 1927. He also won his class once at the Klausenpass-Climb.
3. According to von Frankenberg he resigned from his position at Porsche in January 1933 "a few hours before Hitler came to power, which he must of foreseen together with all the consequences likely to arise;"
3a. von Frankenberg suggests that there was conflict at the Design Bureau between Rosenberger and the engineers over expenses. (Who knows what that means?)
4. Von Frankenberg then goes on to state "he went to America and changed his name." True, but not right away.
5. Also according to von Frankenberg, Rosenberger was involved directly in the design of the Audi Silver Arrow in 1932: "In fact, his [Ferdinand Porsche] technical mind was excited by it [a formula scar of 750 kg] and on November 1932 a calculation sheet came into being, handwritten by Rabe, based on facts discussed by Dr. Porsche, Kales, Rosenberger, and Rabe. The sheet forecast quite accurate technical data for the future Auto-Union racing car; A V-16 engine, with cylinders set at an included angle of 45 degrees; maximum Rpm at first 4,500 (to be increased later to 6,000), maximum speed of 182 mph, bore 68, stroke 75 mm, cubic capacity 4,358 cc, 7:1 compression ratio.
German Grand Prix, Rosenberger was involved in one of the numerous accidents in treacherous conditions. He survived a crash into the timekeepers' box, but killed the three occupants."

6. According to Wikipedia: His successes and records included wins at Avus, Stuttgart Solitude in 1924 and 1925, the Kasseler Herkules Hillclimb and the Klausenpassrennen. At the 1926 
7.According to Wikipedia: "Despite Rosenberger's contribution to the development of German automobiles and German auto racing when Hitler came to power in Germany Adolf Rosenberger, a Jew, was arrested for  racial crimes, and imprisoned at KZ Schloss Kislau near Karlsruhe. He was released, supposedly due to unconfirmed efforts on his behalf by Dr. Porsche, but he was forced to leave Germany immediately. He emigrated to France, and later to Great Britain, representing Porsche GmbH in both of those countries. He immigrated to the United States in 1939 and in 1944 he became an US-citizen under the name of Alan Arthur Robert. He moved to California where he was active in motorsports and the automobile business. He died in Los Angeles, California in 1967.

During the Nazi era, the role in the auto history of many Jews like Adolf Rosenberger, along with Josef Ganz, Siegfried Marcus, and Edmund Rumpler was written out of history."

7a. 

NAME:	Adolf Rosenberger
ARRIVAL DATE:	11 Jan 1938
BIRTH DATE:	abt 1901
BIRTH LOCATION:	Germany
BIRTH LOCATION OTHER:	Pforzheim
AGE:	37
GENDER:	Male
ETHNICITY/ NATIONALITY:	French;German (French)
PLACE OF ORIGIN:	France
FRIEND'S NAME:	H J Roeder
PORT OF DEPARTURE:	Le Havre, France
PORT OF ARRIVAL:	New York, New York
SHIP NAME:	Ile De France
SEARCH SHIP DATABASE:	Search for the Ile De France in the 'Passenger Ships and Images'

8.According to an article written a few years ago in Der Spiegel;

"Rosenberger, of Jewish heritage, had joined the company with Ferdinand Porsche and Porsche's son-in-law Anton Piëch in 1931. He eventually fled from the Nazis to the US, where he ended up unemployed. Piëch, father of VW's current chairman of the board Ferdinand Piëch, was a staunch Nazi, but apparently had nothing against using Rosenberger's money, which "secured survival" for the company during that period, according to Dieter Landenberger.

After the war, a great deal of back and forth finally led to a settlement between Rosenberger and Ferry Porsche. Porsche had to pay Rosenberger 50,000 marks and in addition provide him with a Porsche sportscar or VW sedan until the end of 1950."
9. From:http://www.historicracing.com/driver_az.cfm?type=drivers_alpha&tStartRow=1&AlphaIndex=R&driverID=3283

Anyway with his release came the proviso that he had to leave Germany immediately. He went to England as he had there some commercial interests and he knew a doctor who lived in London because after the weeks in prison he needed treatment for very bad eczema on both his hands and his arms. He emigrated to France and in 1939 to the US. Under his new name, Alan Arthur Robert, he succeeded in starting a new life in California, becoming a citizen in 1943.

He lived in Los Angeles and let a fairly simple life. In 1950 he married Anne Metzger, a former secretary of Porsche`s bureau in Stuttgart who, together with her first husband, had herself emigrated in 1939.

In 1946 Rosenberger tried to return to Germany. He found all his family’s possessions destroyed or taken away, his father died in 1942 while also in exile. He lodged a number of lawsuits against Porsche KG and the state for compensation that went on for twelve years. His suit against Porsche was for 200,000 German Marks. The Compensation Chamber of the regional court of Stuttgart suggested a settlement, which eventually both sides agreed to in September 1950. Rosenberger alias Robert was to receive either a VW Beetle and 50,000 Marks or a Porsche car. Without any great satisfaction he went back to California where he lived until his death in 1968.

In 1982 his widow donated his personal assets to his hometown of Pforzheim where they are preserved in the town archive.

Who was Alan Robert, or Adolf Rosenberger. What did he do while living in California? Any help on this would be most appreciated!

Thanks to Terry Ryno for information!

Photo of Rosenberger taken in the 1920s

Rosenberger and the wheel of the Benz Tropfenwagen

f Ferry Porsche (left) and Adolf Rosenberger (right) sitting in the Maikäfer prototype (1931) | Front cover of Motor-Kritik issue 21 from early November 1931 with the picture of Porsche and Rosenberger in the Maikäfer

Wanted: more information on this man's life!