Ans: In order to be able to manage your polls, you must login to Poll Widget and then create your poll. All polls created by you will be available in the Admin section for tasks like stopping voting, etc.
Ans: If you enable restriction of multiple voting by IP, the system will perform more strict checking to prevent multiple votes. If most of your target audience is behind a proxy or firewall in an organization (like a company or a university), then it is advisable that you disable this feature else many users may not be able to vote.
Ans: Currently, there is not limit to the number of votes allowed on the polls.