[PyMOL] show_bumps.py ?

I have been able to use this script successfully in the past but now for some reason I cannot. I load my structure and in the command line type
run show_bumps.py
show_bumps (selection of what I want to show bumps for), showbumps

and while I get a vanderwaal strain printed out on the command line, I do not get any  disks to show up to illustrate the bad/good contacts (like i do with the mutagenesis wizard).  Maybe I am typing my selection in wrong? So for example, if I want to see any steric clashes residue 6 has with surrounding residues in my structure, I would type in
show_bumps resi 6, showbumps

Thanks in advance.