Hi Hector,
I have problems with translation too. I am using Poedit for translating and before this update everything was fine. But now with version 2.3.6 the code in wordpress-popular-posts.php is displaced and .po file can not locate the words correctly.
I have tried to change the code by myself, but now you are using new function for words view and views in stats: _(‘1 view’, ‘%s views’, intval($pageviews), ‘wordpress-popular-posts’),
As far as I understood from Google this part of the code should start with __(‘message’)or _e(‘message’). In the previous version of WPP you was using __(‘view’, ‘wordpress-popular-posts’) and everything was good. But now with those changes it is not possible to translate the words view and comments.