Genymotion seems to work well for me. I installed it for the purpose of running the Canon CameraWindow app, but I haven't yet figured out how to enable wifi on Virtualbox (on which genymotion runs) so haven't been able to use it to download my photos yet. I assume this is what you're trying to do aswell? Or is there another CHDK related use for an android emulator that I'm not aware of?
