There are two flavors of CSV file reports you can generate from your SERPs account.
1. Only list top ranking URLs (I only care about my top URL!)
2. List all ranking URLs (great for seeing when you rank #1 and #2 for a keyword)
Generate a CSV with only the top URLs for each keyword
Click the 3rd option in the the "Reports" dropdown menu in your "Keywords" tab.
That will download a file like this that shows one keyword per row:
Generate a CSV that shows all URLs that rank
To generate a CSV report with all URLs that rank for each keyword (this could be big!), click the "CSV Export (all URLs)" option:
That will download a CSV that list all the URLs that we found (in Google) that rank: