Greetings. Here's what I know.
The Shawnee started out service as a coastal liner with the Clyde line serving largely between New York, Florida and the Caribbean. She was launched in April 1927 and was sister ship to the SS Iroquois (later the Hospital Ship USS Solace during WWII and even later the SS Ankara after the war up thru the end of the 70's). During her heyday, the Shawnee was considered a fine ship. Babe Ruth himself voyaged on her in Feb. 1931.
When war broke out in Europe in 1939, the Shawnee was chartered briefly by the US Govt. to help repatriate Americans living there. She continued to serve in commercial service until the US joined the war following the attack on Pearl Harbor when she was taken over for use as a troop ship. She was in the Atlantic theater until early 1944 when she went to the Pacific. She remained in government service until 1946. There are a few stories of her conditions being rather horrid (lice, vermin, ship-wide diarrhea, etc). There are several photos available of her on the Internet helping transport Japanese Americans back to Hawaii following internment. See following example: http://content.cdlib.org/ark:/13030/ft3g5004td/?query=Shawnee&brand=calisphere
Those are the only ones I have found of her during the war.
After the war she was purchased by the Iberian Star Line and renamed "City of Lisbon". That was a short-lived chapter in her life. Following a collision with a cargo ship, she was nearly scrapped but was instead purchased by Yugoslavian interests and renamed the "Partizanka." (Note there have been more than one ship by this name over the years). She operated largely as a migrant ship from 1947 to 1949. She was destroyed by fire (quite likely arson) while undergoing repairs in Split in August 1949.
A good picture can be seen at the following site:
I hope that's of some help.
David Montgomery (grandson of WWII Navy veteran, Dr. Hugh Montgomery - USS Solace, Norco Naval Hospital and Guam Naval Base 18 Hospital)