Question Kunena Poll does not work

Which language is your site on?

it's German, I switched in frontend for testing to English and got the same behaviour

In my humble opinion SCeditor has too many flaws. So why not use Kunena 7.0.4 with CKEditor. You won't have any problems.

I don’t know if this has any bearing on the problems described, but when I look at the Configuration Report on page #1, specifically Kunena integration settings:, I’ve noticed that for ‘Kunena – Community Builder’, ‘Kunena – Joomla’ and ‘Kunena – Kunena’, it doesn’t just say ‘Enabled:’ but there’s a whole list of settings. 

I tried out SCEditor because there were problems to copy and paste html code into the editor field with CKEditor.
SCEditor does a better job in this regard. 
But that's a different problem.
But the other issue:
CKEditor - the poll button is not active when create a new topic, is active when I choose a categorie. (Yes, polls are allowed for the category that is selected by default when creating a new topic.)

I have created an update pack for SCEditor 3 month ago.
github.com/Kunena/Kunena-Forum/issues/10096
which corrects many problems, also the poll options (including edit function).

xillibit informed me, that he include this in the upcoming  v7.1,

I don't know which parts of my update pack he will include,
and also if the new code for the poll (edit) option will be there

So why not use Kunena 7.0.4 with CKEditor. You won't have any problems 

that's unfortunately not true
CKEditor of course is the better editor, but its BBCode plugin is very basic and can not handle 
some old Kunena formats
(If you update an old Kunena version where you have inside images with size attribute the editor won't open)