These are the templates I use for sending to devices.
This one puts the ebook in a genre folder; authors subfolder; series subfolder (if needed) then names the ebook file by series number(if needed) and book title.
Code:
{#folder}/{authors}/{series}/{series_index:0>2} {title}
This one is for large series, also series with multiple authors.
Code:
{#folder}/{series}/{series_index:0>2} {title}
Replace #folder with the name of your custom column.
bernie