I added ajax_comments
I added five start to the comment
When I click on five start, nothing happens. I get a 500 server error.
When I look in Chrome, I see the following link which has the error

https://mysite.com/rate/vote/js?widget_id=1&content_type=comment&content...

When I paste it into the url, I get this:

PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'previous_value' in 'where clause': SELECT votingapi_vote.* FROM {votingapi_vote} votingapi_vote WHERE (entity_type = :db_condition_placeholder_0) AND (entity_id = :db_condition_placeholder_1) AND (value_type = :db_condition_placeholder_2) AND (tag = :db_condition_placeholder_3) AND (previous_value = :db_condition_placeholder_4) AND (uid = :db_condition_placeholder_5) ; Array ( [:db_condition_placeholder_0] => comment [:db_condition_placeholder_1] => 11 [:db_condition_placeholder_2] => percent [:db_condition_placeholder_3] => sng_vote_media [:db_condition_placeholder_4] => [:db_condition_placeholder_5] => 1 ) in votingapi_votingapi_storage_select_votes() (line 231 of /modules/all/votingapi/votingapi.module).

I don't know where 'previous_value' is coming from.