In general I agree with Farkel's answers, but I'll add some corrections and expansions.
: 1) How did it come about that Knorr was made president of the WTBTS in 1942 after the death of Joseph Rutherford? Rutherford as we know was an usurper inheritor of Russell's WTBTS in late 1916 after Russell went to his reward. Since Rutherford knew he was dying in 1942, did he try to extend his influence beyond the grave and so hand pick Knorr in a hope to retain the policies at the time?
Actually Rutherford, shortly before his death, called Nathan Knorr, Fred Franz and Hayden Covington to Beth Sarim in San Diego to issue his dying wishes. He instructed them to carry on the work he had begun, thus passing the mantle of power, as it were, to them. Covington became the Society's president, but very shortly thereafter Knorr convinced him that, because he was not "anointed" and Knorr and Franz were, Covington should resign and let Knorr become president. Thus it appears that Rutherford appointed Covington to be the president, despite the latter's "earthly hope". If that were not the case, Knorr would have immediately assumed the presidency. In the late 1950s Knorr and Covington had a major falling out and the latter was basically booted out of Bethel.
: 2) Is it accurate to say that Knorr was nearly single handedly responsible for the prohibition on blood transfusions?
No. Fred Franz loaded the gun and Knorr shot it off. Knorr basically didn't give a rat's ass about doctrine, unless doctrine had something to do with managing his printing plant. The blood doctrine appears to have been Freddie's baby from the beginning, as is apparent from the writing style of the seminal WTS articles on the blood transfusion ban.
: 3) Is it accurate to say that Knorr was nearly single handedly responsible for the establishment of the modern shunning doctrine?
Again, no. Both Knorr and Franz played big parts in it.
: 4) There was a report that Brooklyn Bethel residency was off limits to married people -- until the day that Knorr got married. Is this true?
Yes. It appears that Knorr, for reasons that many have speculated on, decided to get married. Until then it was a very basic Bethel rule that if you wanted to get married, you had to leave. As soon as he married Audrey Mock, he had to allow others to get married, but the restrictions were heavily biased so that only long-time Bethel staffers could make it.
: 5) There was also a report that Knorr was a closeted homosexual, and that his marriage was a sham and a cover-up. Is this accurate?
Many have felt that Knorr displayed rather effeminate qualities, and it is certainly true that some of his closest Bethel associates -- but not all -- were quite effeminate. Whether that indicates latent homosexuality is anyone's guess. Knorr was definitely obsessed with sex, which is likely what drove the Society today to be obsessed with sex. They have more rules on how to deal with fornication and adultery than on any other subject. Knorr's obsession came out in the many WTS articles dealing with masturbation. He was famous for delivering a lecture from time to time to new Bethel boys about how to avoid touching "it" when they "went to the bathroom". I've been told by Bethel insiders that Knorr never consummated his marriage, considering sex to be beneath his station. Supposedly it took Audrey a long time to get used to the idea of a celibate marriage, but apparently she did and became one of Knorr's fiercest defenders.
: 6) Where is Knorr buried? I doubt if he has a pyramid grave site marker like Russell, but it still might be interesting to get a photo on the web. For that matter, where are Rutherford and Fred Franz planted?
I think Farkel is right on Knorr and Franz. According to one source, the man who bought Beth Sarim from the Watchtower Society in the late 1940s told him that Watchtower officials told him when he bought the place that Rutherford is buried underneath the relatively new garage floor. When someone inquired of the owner if he knew where Rutherford was buried (there had been a rancorous fight between WTS officials and San Diego officials about burying Rutherford on the property), he said, "You're standing on him." He was standing on the concrete garage floor at the time. This wouldn't surprise me at all, given the Society's penchant for ignoring "Caesar" whenever they think they can get away with it.
: 7) If Knorr was responsible for most of the post 1942 quack medicine and disfellowshipping teachings, do you think he has more blame for total human suffering than all the other WTBTS leaders put together?
That depends on what you mean by "responsible" and "blame". As the despotic leader of the WTS, Knorr was ultimately responsible for whatever it did. However, he deferred to Fred Franz in doctrinal areas. And of course, plenty of toady underlings went along with anything and everything those two idiots did, so in a real sense, all WTS officials are responsible for those odious teachings.
: 8) Why do you think that Knorr established the general policy on anonymity for WTBTS writings?
Probably several reasons. Farkel touched on a good one. Another is that Knorr was a rather poor writer, and he knew it. He couldn't hope to live up to Rutherford's standards, and so instead of having various staff writers get the glory, he may well have figured that no one would. This is particularly reasonable since it's virtually certain that Fred Franz largely ghost-wrote Rutherford's books from the 1920s onward. It would hardly do for Franz to get a lot of credit by having his name on various Knorr-era books, and then for people to compare the quality of writing of the two men. Knorr was jealous of his power and his prestige -- he had a giant ego. Franz naturally gave in to this since Rutherford had not appointed him, but Covington to lead the pack, which leadership then went to Knorr. If anything, Freddie was a stickler for "the theocracy".