Hi Xiang-Jun,
I don't know if we did something wrong but I got the impression that Frame_mol is handling in a weird manner DG nucleotides.
This means that although all other DNA or RNA nucleotides align well, DG does not.
Here are some files for checking.
and the command line
frame_mol -$numan ref_frames.dat $nucleo_filepath.base.pdb $nucleo_filepath.base.pdb
I checked the variables.
Can you check on your side ?
Best,
Pascal