Some questions got the axe from at least one person.
I'll dig out the comments sometime when I'm not so annoyed with this computer.

5a. How did Colin Creevey and the others die? -- 333333222110X = 26
3f. How did Voldemort assume the form of a baby in GoF when he previously had no form? -- 33333222211XX = 25
3g. The ring... had such a terrible curse; why were the others so easy? -- 333332211111X = 24
3i. Explain again why Harry didn't die (page 709). Or did he die and come back? -- 3333332210XXX = 23
5l. Harry put the Elder wand “back where it came from.” Where? (page 749) -- 3332222222XXX = 23
5m. On the US cover of Deathly Hallows, where are they & what are they doing? -- 33333322100XX = 23
6e. Have you created a War Memorial? A funeral season? Tell us how they all went. -- 333332221100X = 23
3h. Please explain Voldemort’s “stunted form we witnessed in King's Cross." -- 333322221100X = 22
6j. Does Draco still dislike Harry even though Harry saved his life? -- 333322211110X = 22
3c. What happened to Voldemort's last dead body after they moved it? (page 745) -- 333322211100X = 21

5f. George in DH, Draco in HBP were injured by the "Sectum-sempra" curse. Snape healed Draco. Was Snape the only wizard with such knowledge? How was Hermione healed in OoP? -- 33322221111NX = 21
(Note: And who healed Hermione in OoP?)

6c. Did Ron become an auror or work with George in the joke shop? Or both? -- 333222211110X = 21
5c. Did Neville's grandmother survive? -- 322221111110X = 17
4d. Remember the "Ron is Dumbledore" theories -- What was all that about? -- 33222111100NX = 16
5b. How did under-age Colin get back into Hogwarts? -- 332111111000X = 14
5e. Did Fudge get his comeuppance? Azkaban? -- 222211111000X = 13

====================

A = Answered adequately
Q = I still have related questions
C = See my comment
N = No Answer

8a. Why did Dumbledore send Harry after the Hallows... only to distract...? -- AAAAAAAAAAQQC
8b. What was "The Bribe" in chapter eleven? (Locket from Dung to Umbridge?) -- AAAAAAAAAAAAA
8c. Did the locket horcrux have an effect on Umbridge... pure evil anyway? -- AAAAAAAAAAAQQ
8d. What did the Dementors make Dudley see? (JKR answered) -- AAAAAAAAAAAAQ
8e. How did Lupin and Tonks die? (Dolohov & Bellatrix) -- AAAAAAAAAAAAQ
8f. Did Umbridge get her comeuppance? (Yes) Azkaban? (Yes) -- AAAAAAAAAAAQN
8g. Who was the squib who learned magic later in life? (Nobody) AAAAAAAAAAACN
8h. How did Aberforth get the mirror? How often did he check it? (pg 560) -- AAAAAAAAAAAQN
8i. Did a relationship develop between Luna and Dean? (No) -- AAAAAAAAAAAAA
8j. Has Hermione made any progress with S.P.E.W.? (Some) -- AAAAAAAAAAAAN
8k. Is the Quibbler up again (Yes) and is Luna running it? (No) -- AAAAAAAAAAAQN
8l. Is Snape's portrait in the Head's office? (It will be.) -- AAAAAAAAAAAQN
8m. Did Azkaban continue to employ the Dementors? (No) -- AAAAAAAAAAAAN
8n. Is Harry related to Salazar Slythrin? (Gaunt related to the Peverrels.) -- AAAAAAAAAAAQN