Hi,
This is a screenshot of the (not yet complete) Various tab.
The main function is:
void stash_setup_treeview(GPtrArray *group_array, gboolean variable, GtkTreeView *tree, GtkLabel *label, GtkContainer *container);
group_array - obvious
variable - display/edit the groups marked as "variable" [write_once] or all.
tree - obvious
label - if not NULL, displays the currently selected setting name.
container - if not NULL, when a setting is selected, an edit widget is created, based on the setting type and inserted into container. If NULL, there is no editing.
Currentry prefs.c calls stash_setup_treeview(pref_groups, TRUE, widgets-obtained-from-the-Preferences-dialog). But we may call it with, say, an array of plugins groups and FALSE. :)
Hunting the VTE/vc usage took me some time, I'll call it a day. Unfortunately, vc requires some fixing.