just picked up samba de amigo at bestbuy for 5 dollars a few days ago. but cant get past the calibration screen. It doesn't let me skip it either.
Found this over at Gamespot:
"There is a specific wiimote/nunchuck possition for each maraca position. If you have to place both maracas in the middle left side, you have to point your left hand to the left as normal, and the right wiimote/nunchuck has to face left too but with its back facing the tv (the B button of the wiimote has to face the TV)."