Insert in articles?

can I insert your like/dislikes in the middle of an article

Yes, use shortcode: https://likebtn.com/en/wordpress-like-button-plugin#shortcode

How much is the cost of your pro version?

See Plans: https://likebtn.com/en/#plans_pricing

Thank you. It looks like you have a good system. But is it a fact that all voting brings the visitor to your site in the same manner as SurveyMonkey and SurveyGizmo? If I have an average of five votes/page, I expect that all the i/o and linking back and forth from your site would make the user experience too sluggish. Is there some way to “collect” all the votes on my site and then send them to you all at once in a batch, with an acknowledgment of receipt sent back to me? If not, I recommend this enhancement.

If end users are registered on site, do they have to log in again on your site?

Meanwhile where is the rest of your documentation, regarding installation and usage. For example–these are presales questions–what is the syntax for presenting a typical like/dislike, can vote totals be hidden next to the buttons so that voting is not influenced by previous votes, and can total votes (from all questions) be listed in a table on a page chosen by the admin?

But is it a fact that all voting brings the visitor to your site in the same manner as SurveyMonkey and SurveyGizmo?

Votes are stored in LikeBtn.com system. Users do not have to register on LikeBtn.com in order to vote.

Is there some way to “collect” all the votes on my site and then send them to you all at once in a batch, with an acknowledgment of receipt sent back to me?

No.

If end users are registered on site, do they have to log in again on your site?

No.

what is the syntax for presenting a typical like/dislike

Go to “Buttons” tab of the plugin and configure the button or use shortcode https://likebtn.com/en/wordpress-like-button-plugin#shortcode (see available options: https://likebtn.com/en/#settings)

can vote totals be hidden next to the buttons so that voting is not influenced by previous votes

Go to “Buttons” tab and uncheck “Show votes counter” checkbox.

total votes (from all questions) be listed in a table on a page chosen by the admin?

You can try to use Most Liked Content widget provided with plugin or use the shortcode: https://likebtn.com/en/wordpress-like-button-plugin#most_liked_shortcode

Also see:
https://likebtn.com/en/faq
https://likebtn.com/en/wordpress-like-button-plugin

Thanks. Not to appear argumentative, but what about the issue of constant back-and-forth traffic that could make the user experience too sluggish? I assume that every time a user votes there is unavoidable delay while linking to your site; then to come back to my site, to continue reading, would entail another day. The next vote and every new vote would repeat this process, and I would be blamed for the delay, not you. Even if you have a fast connection, there are too many uncontrollable events on the Internet to expect the user to link back and forth up to 100 times in a session, as I would need. Correct?

Nope.

Like Buttons are loaded asynchronously (https://www.w3schools.com/tags/att_script_async.asp) and requests to the server are also sent asynchronously (https://en.wikipedia.org/wiki/Ajax_(programming)) without interfering with the display and behavior of your site, so user can continue reading while buttons are being loaded or voting request is being sent to the LikeBtn.com server.

Also see: https://likebtn.com/en/faq#connect_to_the_server

Enjoy!