  We show that multichannel quantum defect theory (MQDT) can be applied
successfully as an efficient computational method for cold molecular collisions
in Li+NH, which has a deep and strongly anisotropic interaction potential. In
this strongly coupled system, closed-channel poles restrict the range over
which the MQDT Y matrix can be interpolated. We present an improved procedure
to transform the MQDT reference functions so that the poles are removed from
the energy range of interest. Effects due to very long-range spin-dipolar
couplings are outside the scope of MQDT, but can be added perturbatively. The
new procedure makes it possible to calculate the elastic and inelastic cross
sections needed to evaluate the feasibility of sympathetic cooling of NH by Li
using coupled-channel calculations at only 5 combinations of energy and field.
