Just a quick aide memoire in case it is useful to anyone. Sometimes in the past I have hacked away at navigation-procs.tcl to suppress parts of the breadcrumb trail (which is generally a bad idea!)
This css rule will cause only the parent node of your current location to be visible. This could be useful for creating a 'back' button for example:
#breadcrumbs li:not(:nth-of-type(2)) {display: none;}
R.
