Default Format: Here you can choose the data format you wish to export your invoices to, between XML and JSON. Different systems accept different formats, so make sure that you know what format is accepted from the system you will import to and set it here.
XML Charset: With the checkbox checked, the resulting XML file will use the charset of your WordPress installation. If you uncheck the box, you will be able to enter the charset of your choice in an input field to be used instead. UTF-8 should be recognized by most systems but in case yours requires something different, you can set it here (XML format only).
First you need to set if you want to override the recipient information if it already exists in your installation. If the box stays unckecked, the imported recipient's info will remain as-is in your installation. If you check it, the info will be replaced by the one on the invoice. After this, you need to set how to handle recipients who do not exist in your installation. By setting the "If Recipient does not exist" dropdown, you can chose between creating a new recipient (with the info from the imported invoice) or use an existing recipient (from your system) for all imported invoices where the recipient is unknown to your installation, by setting the email of the user you want to assign the invoices to.
Finally, you can set the user role that will be assigned to newly created recipients, in the last dropdown.
Another functionality that the Power Tools for WP-Invoice provides, is the ability to visualize your sales, filtering sales by day, week or month and view your sales chart in different zoom from 1 day to all time your existence.
You can find this button on filter box of your invoices. You also will have ability to visualize your sales, filtered by type, status, recipient and date of payments.