For KG 200 pictures in general, seek out “KG 200, The Luftwaffe’s Most Secret Unit” by Geoffrey J. Thomas and Barry Kettle (Hikoki Books). Also, using the search facility on this site should bring you A3+MD, a Ju 188 that served with 4./KG 200 plus (from memory) one other.
Dr. Günther W. Gellermann published a photo of another 4. Staffel Ju 188 about 30 years ago but unit markings are not visible. It does have a black underside though. An intelligence report on A3+QD (crashed in Holland, January 1945) suggests entirely conventional bomber camouflage.
There’s a list of 4./KG 200 Ju 188 Werk Nummern and markings here:
http://ghostbombers.com/Olga/olga_loss.html