Comments addon not showing in the page, but yes in the addon

Gooday,
I have not option to add Comment addon in the page; it is not available between the addons.
But in the Addons list it appears.
In SP Page general settins it is enabled: Comment must be manually approved
I have installed Jcomments but it only appears in the bottom of the page, i would like to show comments inside a section.
I have installed RS feedback but it is hanged out on the components, so i can not insert inside SP Page; neither as iframe: it crashes.
I appreciate any help.
Thanks.
Best regards.