...Don't ever ask for level 100 Zapdos. That's your first problem. ;D Next, since the error message never came up, you must be turning off the DS too late. You have about a one second gap to turn off the DS and it'll clone correctly. I suggest turning off every computer, Wii, DS, whatever to make sure it's not using the internet to make it stable. Then try turning it off at about 7, 8, or 9 spins. If you do too early, your pokemon never goes through. At the right time, it'll go through but it'll back up your save file and show the error message. It depends on your internet... It might work at 17 seconds (real time clock, not DS thing) since that's what it does for me but I have a high speed connection. But if you just have a wireless router, turn off when it blinks. Not many people have one so just stick with guessing and luck.
I think they're already threads like these but oh wellz. -.-