I've managed to install and I get only the top pane of the EditSurvey page (as in your screen capture), but I get no add/remove question buttons, just SAVE and CANCEL. What could be wrong.
JS console display this warring:
This page is using the deprecated ResourceLoader module "jquery.ui.core". Please use "mediawiki.ui.button" or "oojs-ui" instead.
$egSurveySettings['JSDebug'] = true;
Don't display any additional information.
Survey-REL1_30-55c6b62 , MW1.30 , PHP 7.0.26
Any idea?
Thanks