This file is not used by the engine - it is left over from BG1. The starting abilities filenames (SPIN101 throuugh SPIN106) are coded into the executable and are assigned on a probability scale based on character alignment.

In BG2 ToB we have:

2DA V1.0
SPIN103
           1          2          3          4          5          6          
L_G        SPIN101    SPIN101    SPIN102    SPIN102    SPIN103    SPIN103
N_G        SPIN101    SPIN101    SPIN102    SPIN102    SPIN103    SPIN103
C_G        SPIN101    SPIN101    SPIN102    SPIN102    SPIN103    SPIN103
L_N        SPIN101    SPIN104    SPIN102    SPIN105    SPIN103    SPIN106
N_N        SPIN101    SPIN101    SPIN105    SPIN105    SPIN103    SPIN103
C_N        SPIN104    SPIN104    SPIN102    SPIN102    SPIN106    SPIN106
L_E        SPIN104    SPIN104    SPIN105    SPIN105    SPIN106    SPIN106
N_E        SPIN104    SPIN104    SPIN105    SPIN105    SPIN106    SPIN106
C_E        SPIN104    SPIN104    SPIN105    SPIN105    SPIN106    SPIN106