The config gives the following format info for this entry, but I've tried several permutations, including the one below, and keep getting crashes, apparently I'm not formatting it properly.

#List of items to always keep, drop, or destroy, regardless of other settings
#Format: modid:item;[keep/drop/destroy]
itemSettings = []

" itemSettings = antiqueatlas:antique_atlas [keep] " seems like the proper way to do it, but doesn't work.

Could you provide an example of how this should be properly formatted?

This worked! Thank you!