I had trouble, back when I had Pythons, getting them to eat FT too. I used to dip them in chicken broth and then put the FT in a shallow tupperware container big enough for the snake to get into and then flop the snake right on top of them. Gulp every time.

Some say that BP are shy animals and need a week or two to adjust, but I never had any such issues with them, which is not to say it is untrue. Pythons in general can be very picky eaters most of the time and a FT mouse doesn't have the same smell as a live one, thus the Chicken broth helps them a lot.

~Jim