Restricting votes

Hi! I really loved using your plugin – we used it for displaying GIFs created based on artwork. However, since I am on the free version, a lot of people voted using multiple sessions [same IP address] registering around 1600 votes on one item too! 🙁

This made our website crash – high ajax count – I have had to deactivate the plugin for now, but is there a way to solve this? I would like to keep the voting open till Monday, August 10.

Alternatively, can I check how many unique votes each item received?

I would appreciate your support. Thank you!