though i feed my BP live, I would not recommend you feed it live(due to your preference of F/T), not just yet...check his weight every week, making sure it doesnt go down...once it does and he's still refusing then i will try live...
Also, the f/t may not be the right temperature...make sure you check the f/t belly for any cold spots and also make sure your thawing method doesnt make the mouse too warm either...
Good Luck...