You can register using either your Salesforce credentials (oAuth), or with an email and password. Head over to https://app.dataimporter.io/register, choose the server that you would like to work with and complete the registration.
No you don’t. We have a Free Tier which is only limited by the number of records that you can process (20,000).
Yes you can, simply head to the Instance page and click on Login to Production or Login to Sandbox.
There are lots of different errors you can receive from Salesforce. We have an article of 10 of the most common ones to help you out Here, otherwise feel free to email us and we will do our best to help.
Yes you definitely can! When on the mapping screen, search for the lookup relationship, and choose the Salesforce field that you would like Dataimporter to lookup the records via.
If you have inserted records, head over to the Successful Records page, and up the top you will see a Rollback button. If you click on this, and then confirm, Dataimporter will automatically delete the records for you, without having to download the CSV file, and create a new job.