in gravity.m: removed setting the static_model property to empty before calling common_ops; added check for exception on the value of the static_model property inside common_ops.
in gravity.m: removed setting the static_model property to empty before calling common_ops; added check for exception on the value of the static_model property inside common_ops.

jgte/orb,jgte/orb,jgte/orb,jgte/orb,jgte/orb