Template is loaded, but the <script> does not load from it.
Tize, find template captcha_qaptcha your forum style in the admin panel and post here the contents of the template.
When installing KeyCaptcha uses overwrite standard class Captcha settings for guests and it is not correct. I have a few months ago reported it to the developers KeyCaptcha, but the problem also seems actual ...
Thank you for your comment and evaluation addon :)
As for your question, in the current version of the addon a multi-use spam checks are not implemented. I do not see reason in this. Why make things difficult for the user?