1 - You run the firmware update, not the kernel/Wood one.Well, crap. My R4i Gold 3DS doesn't work on the latest update. Even after I tried to update the kernel. I"m thinking about buying a DSTWO, but now I'm hearing about the CPU drain.
what to do
2 - The normal drain isn't nearly as large as people make it out.
http://gbatemp.net/threads/the-ultimate-ds-battery-test-thread-in-the-world.289020/
3 - The drain in "sleep mode" is because the DS doesn't have a sleep mode, it just turns the screens off and tells the game to shut up. The same happens with legit games. I can be playing my retail SoulSilver cart on my DSi, shut the lid, sleep, wake up and it's in the red.