The available evidence points inexorably to the conclusion that Baden-Powell was a repressed homosexual [...]Among other things, it is known that he enjoyed watching young men swim naked and that he expressed disdain for seeing female nudity. Baden-Powell also had a decades-long friendship with Kenneth McLaren, with whom he served in the military and with whom he shared accommodations as often as he could.
http://gaytoday.badpuppy.com/garchive/world/040397wo.htm
However, according to Patrick Higgins' 1993 book, "A Queer Reader": "In recent years two authors have suggested that Baden-Powell may have been homosexual. Neither offered any evidence, and both based their supposition entirely upon a shared suspicion that his relationship with (his longtime friend) Kenneth McLaren might have been a physical one."
On Nov. 15, 1919, McLaren wrote in his journal: "(We) stayed with Tod. Tod's photos of naked boys and trees, etc. Excellent." Three days later, in a letter to A.H. Tod, Baden-Powell wrote, "Possibly, I might get a further look at those wonderful photographs of yours?"
Admittedly, not the best sources, but I couldn't find anything out there refuting them or any other info...