Hi bill-hilly,

I guess you will not find the typical Slapping-Bass sound on BiaB.
It would be the best to record the bass on the bass line and on the drum line put some "clicking" sound for the slapp.

Count:
1 + (1+, 2+, 3+, 4+...)
Bass - Slapp-Click

or
1++, 2++, 3++, 4++


Hope this was helpfull.