If you are getting this error...

Warning: Creating default object from empty value in /home/user/public_html/modules/mod_random_image/helper.php on line 85

.. then it could be that php on your server was upgraded from 5.3 to a newer version. From 5.4 onwards they tightened up the rules.

To rectify - you need to define your new object before you start using it.

In the code, above the line one stated in the error message (Line 84), add...

$images[$i] = new stdclass();

Or for Event List (line 164)...

$this->_event = new stdClass;