Thread:Extension talk:ConfirmEdit/QuestyCaptcha works - but only with trigger "createaccount"

I'm managing a small musicological wiki (http://liturgica-notata.wiki.gwdg.de) and trying to keep it spamfree. I've installed several extensions, and the most effective so far seems to be QuestyCaptcha with some really special questions.

What bothers me is: QuestyCaptcha seems to be only triggered by "createaccount", though in the LocalSettings.php I have specified it to be triggered by "edit", "create", "createtalk", "addurl", "createaccount" und "badlogin"; "skipcaptcha" is "false" for "*" und "user" and true for "autoconfirmed". As an unregistered user, I can create and edit articles and talk-pages without captcha ("addurl" and "badlogin" I didn't try out).

What can be the cause for that funny behavior? And how can I change this? As all spammers in my wiki so far did create accounts, it is no serious problem, but I'd like to protect the other kinds of actions as well.