Use the New threads widget and add the widget in the template of your page.
If you want to show threads from a specific forum you can go to admin.php?widgets/ and create a new widget with the desired parameters.
1. I'm not completely sure but you can take a look at src\XF\InlineMod\Thread.php
2. You can see how is do it for the others actions in src\XF\Pub\Controller\Thread.php, a good example is the function actionQuickClose.
Update to the latest version and getting this error in the browser console when trying to load the ratings tooltip.
jquery.min.js:2 jQuery.Deferred exception: Cannot read property 'tooltipDelay' of undefined TypeError: Cannot read property 'tooltipDelay' of undefined