Actually, in docking2 docking_local_refine job 17790, the 20 decoys with the most negative I_sc values have total_score=-106.625 to -107.714, rms=9.699 to 17.262, Fnat=NaN, I_sc=-0.037 to -0.81, and Irms=0.322 to 2.164. Meanwhile, in docking2 local_docking job 17791 (based on the same initial pdb file as job 17790), the 20 decoys with the most negative I_sc values have total_score=-105.021 to -110.599, rms=9.915 to 26.312, Fnat=NaN, I_sc=-2.858 to -3.549, and Irms=0.731 to 6.706.
Does this information change what you think causes the Fnat=NaN results?
Thanks!