[Ifeffit] error in ATOMS

Hi Bruce, Here's the screen shot of my work in ATOMS. It's supposed to be more than 7 atoms in the core column but that's also one thing I do not know how to add change and add more atoms. When I click "Run Atoms", it gives me this error "Can't call method "tag" on an undefined value at C:/strawberry/perl/site/lib/Demeter/Atoms.pm line 668.'' I am using the recent version 0.9.18.2 of the Demeter installer. Thank you for your help! Julius