Here's a web page with several photo's
http://www.ijaafphotos.com/jbwki561.htm
"Rod's warbirds"; note the code name was Thalia not Thalla as on that page. I believe either the second from left or furthest right photo is the one in Francillon, but one of the others shows a camo scheme (in black and white).
Here's a Japanese page showing the box of a model kit for a Ki-56 with similar scheme in color; ninth row down.
http://www.fenyworld.com/shala/hikouki5/hikouki5.htm
For technical description, I don't know of anything better than the entry in Francillon.
For operational use the plane is probably best remembered for the IJA parachute assault on Palembang, Sumatra in Feb 1942.
http://www.geocities.com/dutcheastindies/palembang.html
That page says 34 Ki-56's were used, the Osprey "Japanese Paratroop Forces of WWII" by Rottman and Takizawa says (or implies) the transports were 22 Ki-56's and 12 Ki-57's (Mitsubishi, Type 100 transport, aka MC-20 or 'Topsy').
Joe