Genre subfolder when sending to nexus7

Hi

[Caliber 2.6.0]

I'd like to create a genre subfolder when saving titles to my nexus7.

I'm confused as it seems to be specifiable in two places:

1) Preferences -> Import/Export -> Sending books to devices -> save template
2) Preferences -> Plugins -> Device Interface Plugins -> Android Driver -> save template

I've tried the format "{#genre:subitems(0,1)}/{title}" in both places but the title is always saved as {title}-{author} at the top level. I have "use sub folders" enabled in the Android Driver plugin config.

Also, what would the syntax be to integrate 'ifempty("unknown")' into the above so if subitems(0,1) is empty the top level would be "unknown"?

Thanks!