Yes, data from the Merchant Backend can be downloaded as a CSV file. You can find the download options under the respective menu item.
The following data can be downloaded:
Customers
Reports
Payout Lists
All data can be filtered by a specific time period before exporting. Each download is limited to 5,000 records.
Invoices and order confirmations can be downloaded individually as PDF files.
Delivery lists and IVW reports can be downloaded from the Downloads section: Downloads