Directory plugin - Categories & Creating more than one in a single website

Hi all
I am running Wordpress 3.4 with your latest Directory plugin.

I have styled my directory mainly using TroycDunn's great suggestions (with a couple of tweaks), but what I can't find out is:
1) If the 'listing-categories' have their own sub-page; and
2) what php code I need to find out which 'listing category' the directory is part of.

I would like this for two reasons, respectively:
1) to create different menu tabs to display only the relevant listings for the different categories. (I have musician, music venue and music producer currently, so create say a 'Musician Listing' page that lists only the directories that have the 'listing category' of musician)

2) So that I can amend my single-listing.php page so that the left-column shows different fields depending on which category has been selected. i.e. use something like if(is_category('musician')) { show these custom fields ;}. Clearly, is_category() is the wrong expression, as this is tied to Wordpress' own categorisations.

Please can you direct me to the right way to do both of these?

Many thanks

Rob