I think part of the problem why cards depcreate packageName results in segmentation faults if cards.conf contains lines like
dir var/lib/pkg/depot/collectionName
is that cards get confused between ports directories and binary packages directories.
The solution would be simple, add a type field to the dir lines.
I think most /etc/cards.conf files should looks like:
#url apply only to dir of type binary packages
url
http://download.nutyx.orgdir b /var/lib/pkg/depot/base
dir b /var/lib/pkg/depot/cli
dir b /var/lib/pkg/depot/cli-extra
dir b /var/lib/pkg/depot/gui
dir b /var/lib/pkg/depot/gui-extra
dir b /var/lib/pkg/depot/desktops
dir p /usr/ports/base
dir p /usr/ports/cli
dir p /usr/ports/cli-extra
dir p /usr/ports/gui
dir p /usr/ports/gui-extra
dir p /usr/ports/desktops
dir p /usr/ports/personal