[dlw]

I need some help with this wonderful software. I have a brand new installation of Rasbian Buster, php 7.3, nginx, and COPS1.2.0 on an rPi zero W. After a few false starts (my first time with nginx, php, and COPS), everything works -- except that I cannot for the life of me display custom columns.

I have three Calibre libraries (Fiction, NonFiction, and Graphics) to split the load across cloud servers. I have no problem defining and using all three of them with COPS, but to keep things simple, I'm only trying custom columns on one -- until it works. I have two "custom" columns in Calibre in all the libraries: DD and DDC. The first I use constantly in the Fiction library to track categories such as "FIC", "MYS", "SF" and so forth. The DDC column comes into its own in the NonFiction library, where it contains an approximation of the Dewey Decimal number assigned to the ebook. These are not composite columns (though I do use them to create the file name for use in Calibre's "save to disk" routine).
No matter what I try, I can't seem to get the columns to show up in COPS. The code I'm using is:

$config['calibre_directory'] = "/home/pi/ebooks/Fiction/"; /* one library for testing */
$config['cops_calibre_custom_column'] = array("DD", "DDC"); /* has no effect */
$config['cops_calibre_custom_column_list'] = array("DD", "DDC"); /* has no effect */
$config['cops_ignored_categories'] = array("publisher","language"); /* works */

Can you think of anything I could try? Or where in COPS code I could see where it's processing -- to see what it actually looks for and finds? (php's not that hard to hack into, is it?)

I did search the forum for people having the same sort of problem. The solutions I found don't seem to apply to me.

Thanks for thinking about this.