What are you trying to record into? Software or hardware?

And what is your sound source? Internal DXI/VSTi or sound module/ synth?

Ultimately, physically or through a software mixer depending on your audio interface set up, you tap into the same output that BIAB sends to your speakers if you are using internal sounds or to the output of your sound modules/ synths if that's what you are using.

For sound modules I have their output patched into my audio interface. BIAB triggers the synths and I use Sound Forge, a wave editor, to record the input to my sound card from the modules.

Prado