Subject: Re: how to create a sum of ranks in GTR
Note that importf does not deblank any fields, even if they are deblanked in the imported screen. Use the default value in importf to deblank. For example, this importf uses a default value of -9999. Use rPE>0 to deblank in the main screen.
importf(0,rPE,-9999)

Also, I have found using rank as late as possible in the main screen has better results generally. Apply any extra criteria before the rank step if possible.