Now it's possible to select which type of voting available for forum.
- Accept Positive and Negative votes from visitors (default)
- Accept only positive votes
You can choose voting type in settings.
Project->Forums->Setup->Voting for a feedback 
Also we added ability to allow users view who voted for the feedback.
You can allow to view votes using  option in settings.
Positive and negative voting
Only positive voting
Customer support service by UserEcho