I'm not sure where it is anymore, I would start with the do_equipment (or something) command and follow the logic. Figure out how it shows this and alter it so it shows the empty spots as well. Sorry, I wish I could be more specific but I'm at work and don't want to browse the code.
The continue keyword is skipping that slot entirely. You can simply remove the conditional statement all together if you want to show empty slots.
Hope this helps.
That conditional check ensures that eq is not null in the following statements. Removing that could be harmful. You may want to simple print "Nothing" or a blank line (ie. "\r\n") at the very least within that conditional check AND then still continue.