I only just discovered how to create custom fields/columns in Calibre and went crazy converting my tags to custom fields/columns for more useful sorting. Alas, I made the mistake of assuming that selecting "Comma separated text, like tags, shown in the tag browser" when creating a new column would mean that my info would still be treated like tags/collections when transferring to my device. Now all my tags/collections are gone off my Sony reader!

That will teach me to make assumptions.
Is there a way to make these custom fields/columns be treated like tags/collections? Or am I just stuck with the old (bulky, clunky) tag organization I had going on before?
ETA: I figured out how to make more than tags and series transfer. I was looking in the wrong place.