Plugin Questions

Hi I have been checking out your plugin and I need to ask a couple of questions about the plugin, after installing the plugin I need to enter an email address in the settings, can I use any email address here?
Also does the plugin send an email every time a customer buys the same product, or does the plugins logic check if the customer has already bought the product and reviewed the product and if so it does not send an email.
From reading the information for the plugin it sounds like the plugins logic blindly sends emails to customers every time they buys something, hence my question.
Any advice will be much appreciated.
Pete
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