'shared host' ...
2 possible issues - one is theme ...
https://moodle.org/plugins/pluginversions.php?plugin=theme_aigne
shows compat up to version 3.0 of Moodle.
The second possible issue ...
folks who are on shared host may have issues in setting
the 'right' character set/collation and file format (Barricuda) for DB for version 3.6.any
https://docs.moodle.org/36/en/MySQL_full_unicode_support
Running the scripts in moodlecode/admin/cli/ might fail as they require a user that can alter DB server config and no one does that on shared hosting DB servers cept tech support of provider.
'spirit of sharing', Ken