If you have BIAB then you also have RealBand.

In Real Band you can import an MP3 or WAV file then play it back at 100% - 75% - 50% or 25% speed

I'm not at my music computer at the moment so I can't tell you the specific commands to get you there, but it's definitely possible in RB. I just used it the other day to loop thru the region of a song that contained the solo. At 75% speed looping thru the solo over and over you can learn a passage very easily.

Note: it doesn't change the pitch, just the speed

update:
from RBs main dropdown menu, select ACTION > PLAY AT SPEED > then pick your speed