madd chemistry

]HEY I RECENTLY BROUGHT THE LATEST VERSION OF A:M BUT I'M HAVING TROUBLE WITH ROTOSCOPING. I'M TRYING TO MODEL OVER FACES I FOUND ON THE INTERNET, AND ALSO ON CHARACTERS I DREW AND SCANNED INTO A:M BUT THE PICTURES DON'T SHOW UP IN THE PROGRAM FOR ME TO MODEL OVER. NO MATTER WHAT I DO I CAN'T GET THE PICTURES TO APPEAR ON THE GRID TO BEGIN TO MESH THE SPLINES OVER LIKE THEY DO IN THE DEMOS AND TUTORIALS. PLLLLLEEEEAAAASSSSEEEEE HELP!!! [THANX