I have inserted in Item view Seblod Form field. Now I have the form shown on the page 10 times under each Item. How do I display under each Item only the "Reply to this topic" button when clicking on which the form would be displayed? On your forum this implemented.
Depending on the template you use for item you should be able to add a Free button in the one of content positions and form embed in the popup position, it might be you will need to add some javascript to make it work.