Are the administrators sessions saved?

Not by default, however through Customer History -> Settings you can choose to enable this funcionality.

Can I see the IP address through which users connect to my site? 

Yes. To do it, you need to enable the save of IP address from the plugin settings dashboard by setting “Yes” in the entry Save users IP address?

My database is too full and seems to depend on the plugin. What can I do? 

The bigger a flow of users, the higher the amount of data stored by the plugin.

You can delete these data and all the emails using the related buttons that you can find in the tab “Settings” of the plugin settings dashboard.

Please note: once deleted, data can’t be recovered in any way.

We recommend making a backup before applying this action.