1) I find emulators to be nearly perfect
2) Yes, you can. It depends on the caanoo itself, not on the SD!
2b) So, if it's defective, you're unlucky, that's all :) Return it so!
4) Oh, come on... 960 on 76800...
1) Did anybody told you that all the emulators are a work of the community?
2) Change your SD card. Then they will work
3) In wich software) Try the button tester in the settings, if it does not work, it is defective
4) Come on! For 3-4 pixels!