Please note that Kickstart extracts the backup archive. Your database is restored by ANGIE, the restoration script which is part of your backup archive. Your problem is in ANGIE, not Kickstart.
This message comes from your server. It literally means that your web server thinks that PHP is taking too long to run.
The solution depends on when you get the message.
If you get the message immediately after starting to restore your database, without the progress bar having moved at all, you need to check the database connection information. If you enter the wrong information it is possible that PHP "hangs" trying to connect to the database server which causes the 504 Gateway Timeout error.
If this happens during the restoration of the database, after the progress bar has moved a little, you can try changing the timing settings. In the Database Restoration page, before you click the Next button, go all the way to the bottom. There's a Fine Tuning section. Set the Maximum Execution Time to 2 and the Throttle Time to 1000.
Please note that if you are on SiteGround the problem comes from their hosting platform. These issues started in early September. They were so bad and there was no commitment to resolve them that we had to urgently transfer our site from SiteGround to Rochen. If you are on SiteGround you will have to tell them about these issue and ask them to be fixed or consider looking for a host where the server doesn't randomly kill PHP processes. This not only makes restoring sites problematic, it is causing errors with otherwise functional sites throwing this error randomly at a rate that varies between making the site unreliable to making it practically inaccessible for everyone (that's the point we reached when we decided to move to a different host). SiteGround used to be a very good host but they have chosen to follow the direction of a mediocre, WordPress-only host lately.
Nicholas K. Dionysopoulos
Lead Developer and Director
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