Hey there, I got a black screen after updating to 10.5 on rxTools, to fix it, I deleted the home menu information, it's a folder that ends in 8f in the Nintendo 3DS folder, to be safe, do this: rename the emunand folder inside the Nintendo 3DS folder (the one with a long string of gibberish, I just added a dash in the front), then put your SD card back into the 3DS and boot up the emunand. It should work, and create home menu information. You'll notice it creates a new folder exactly the same name as the one you renamed, so look what was saved into it, delete that folder in your renamed emunand Nintendo 3DS folder, and then delete the new gibberish folder and rename the old folder back to its original name.
it will gift wrap your games all over again, and mess up the arrangement, but I didn't backup my emunand and doing the above was a lot better than redoing the whole thing again ~__~