Your server returned an HTTP error code 503 Service Unavailable. This means that you have ran out of free space, ran out of bandwidth or your host imposes limits on the number of requests per second you can execute on your site.
In the first two cases there's nothing I can do to help you. You'd need to buy more space or bandwidth from your host.
In the latter case I can try to do something to help you. Before clicking the Start button in Kickstart scroll all the way down and set "Minimum execution time" to 5 and "Maximum execution time" to 1. Yes, the max is less than the min. This slows down the extraction 5 times which should overcome this kind of requests per second limitation of your host.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!