  We study theoretically the formation of long-wavelength instability patterns
observed at spreading of nematic droplets on liquid substrates. The role of
surface-like elastic terms such as saddle-splay and anchoring in nematic films
of submicron thickness is (re)examined by extending our previous work
[Manyuhina et al EPL, 92, 16005 (2010)] to hybrid aligned nematics. We identify
the upper threshold for the formation of stripes and compare our results with
experimental observations. We find that the wavelength and the amplitude of the
in-plane director undulations can be related to the small but finite azimuthal
anchoring. Within a simplified model we analyse the possibility of non-planar
base state below the Barbero-Barberi critical thickness.
