Many months ago I changed the code so the number of labels was not an
absolute limit, but there was always something odd in the code.  I
have finally tracked this down, and now have a version where the
message
        LABELS list is full...extending to xxx
is not a disaster.  The other manifestation of this bug was the
message
        indx=%d (%x); (short)indx = %d (%x)
        indexing overflow error
for some values of %d and %x.

trivial fix is in otran.c, to remove the assignment to nlabels in the
line
    labels = (char **)mmalloc((nlabels=NLABELS) * sizeof(char *));

Then the constant NLABELS in oload.h can be small, like 10 or 20