Hi Alex,
You are welcome to open a support request and we will be happy to help you resolve this issue, we provide quick support and help on the forum and I am sure we can resolve your issue if you contact us instead of just giving bad review.
I did a quick test now, I can confirm that I was able to upload orders from CSV file.
If you decide to change the review and get support first, You can send us on the support, a screenshot of the error message on the page and if you can a screenshot of the CSV file. if you can make sure you are using Google spreadsheets to edit and download your CSV file to avoid formatting issues when using Excel.
Thanks