In response to your questions:
I didn’t see any errors when loading the page (in F12 mode). Please see screenshot.
In regards to the web server error_log unfortunately this was disabled at the time of upgrade (gah!) but has been reenabled. From the php error logs there is the following:
php-error log:
[14-Feb-2017 11:31:11] PHP Warning: copy(/srv/web/www/wp-content/uploads/h5p/temp/h5p-58a2ea7f0e124): failed to open stream: No such file or directory in /srv/web/www/wp-content/plugins/h5p_latest/h5p-php-library/h5p-default-storage.class.php on line 158