A method was recently proposed for calculating state-to-state rotational total cross-sections that involves solving two-dimensional close-coupled equations but takes into account the three-dimensional boundary condition. In this Letter, this proposal is tested on the system Ar-N-2 for a range of potential parameters that control the anisotropy of the system. In particular, the contribution of the long-range force to the cross-sections is investigated. The results are in very good agreement with the three-dimensional close-coupling calculations in the case that the molecule is initially not rotating. In all other cases the results are less satisfactory.