That's unexpected. From the screenshots you shared it looks like you have things set up correctly.
Does the problem only happen with this specific product, or with all products?
To rule out a conflict from some 3rd-party code, could I ask you to test again with all plugins except WooCommerce and Toolset deactivated, using a default theme like twentytwentyone?
We tested the situation in a test environment (WooCommerce and Toolset deactivated with twentytwentyone). Problem is still active (Screenshot from 2023-10-24 12-57-02.png).
After this test, i set up everything back to business.
When I was testing, I observed that when I set the content template named "Blocks-WooCommerce-tuotekortti" to "none", the product gallery and product variable images become visible.
At the last part i switched Block output from Toolset custom's output to WooCommerce Native Output. This change had no effect.
From looking into the page's markup, I understand that gallery images are coming as part of the HTML. But some custom or third-party styles are conflicting due to which they're not showing up correctly.
Can you please share the temporary admin login details, for further troubleshooting? I'll also need your permission to download a clone/snapshot of the website, in case it needs to be investigated on a different server.
Note: Your next reply will be private and making a complete backup copy is recommended before sharing the access details.
During troubleshooting, I was able to fix the product gallery thumbnails, by selecting the 'Horizontal' gallery option at WP Admin -> Appearance -> Customize -> WooCommerce -> Single Product -> Gallery Layout.
( screenshot: hidden link )
I think the problem was caused by the compatibility of the theme and the Toolset with the previously used settings. Hopefully this will be fixed in future updates. Recent updates to the Astra theme may have something to do with this issue.
A solution was found quickly and communication with the support service was smooth. Thanks!