SUBROUTINE KUXB2K(NGAM, ITRK, IPNT, LERR)
 
C  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
C   Put some XBAL photons into the KN list.
C
C   Note: NTRKKN is incremented after every call. It is the user's
C         responsibility to clear it at the start of the event.
C
C *NGAM      Integer variable (read/write)
C            Input:  # of tracks to fill from input track list.
C            Output: # of tracks actually filled
C            If NGAM=0, all tracks are used and ITRK(I) is ignored.
C
C  ITRK      Integer array (read)
C            List of XBAL tracks. Ignored if NGAM=0
C
C *IPNT      Integer array (write)
C            IPNT(I) = positions in KN track list (packed array, not
C                      necessarily in 1-1 correspondence with ITRK)
C
C *LERROR    Logical variable (write)
C            TRUE ==> output track list overflowed
C  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>