The Four Presidents Of The Watchtower by Edmund Gruss is a very insightful book.  This presents some of what the book says, and you are much encouraged to get your own copy.

It appears that Nathan Knorr rose to power by developing an intimate friendship with Frederick Franz, who then promoted him to Joseph Rutherford.   For example in 1923 Franz gave the baptism talk for Knorr.  He also did whatever Franz and Rutherford wanted done, and "hearsay" or rumor is that one such thing was to secretly obtain and have smuggled a lot of liquor from across the border with Canada to an apartment in Bethel where Rutherford could get it.

Another example, according to Gruss, who is excellent in citing various sources throughout his book, pertains to what is called the "Declaration Of Facts."  With help from Franz, Rutherford drew up the letter.  Then in 1933 Knorr helped Rutherford when he went with Franz, taking the letter over the Atlantic Ocean for the Nazi government of Adolph Hitler to read.  Watchotwer's own 1974 Year Book quotes some of the letter which says:

“"The Brooklyn presidency of the Watch Tower Society is and always has been exceedingly friendly to Germany.  In 1918 the president of the Society and seven members of the Board of Directors in America were sentenced to 80 years' imprisonment for the reason that the president refused to let two magazines in America, which he edited, be used in war propaganda against Germany." (Gruss 16, 17)

The Declaration letter also told Hitler and his government:

"The greatest and most oppressive empire on earth is the Anglo-American empire.  By that is meant the British Empire, of which the United States of America forms a part.   It has been the commercial Jews of the British-American empire that have built up and carried on Big Business as a means of exploiting and oppressing the peoples of many nations...... Instead of being against the principles advocated by the government of Germany, we stand squarely for such principles." (Gruss 17)

There were homosexual scandals at the world headquarters in the mid 1950s, during the late 1960s and early 1970s.  Whenever those scandals started to become known too much, Watchtower printed articles against homosexuality, but otherwise did not print articles condemning homosexuality while Knorr was in absolute control of Watchtower. (Gruss 43)

Frederick Franz never married and was often seen alongside Knorr who was younger. It was rumored that they were homosexual mates; eventually Knorr changed the rule against headquarters staff members marrying so that he himself could marry a JW woman, which caused the rumor to die although rumors may have picked up that the marriage was for not real or that he might be bisexual. (Gruss 43)

In one of the "Questions from Readers" articles in a Watchtower magazine, it was asked if a person could get a divorce after a marriage mate had committed homosexuality.  The article answered that they could not divorce since the sex organs of the two homosexuals were the same, which meant that the two homosexuals had never really been able to fit together naturally and so had never actually become as one person.  This was upsetting to some in the organization and so a countering article soon appeared.