Upon further investigation this seems to be a caching related issue, that is because even your X and Cornerstone is up to date, your site (both live and /uusi) are looking for a file on a wrong directory.
/x/framework/tco/js/dist/admin/ is the old directory of the
The new directory in X version 6.3.8 is
These is the reason why you get a weird layout on X panels, X > Validation and X > Settings
Another thing, this kind of broken layout is commonly happening if you have an outdated version of Wordpress, but I see your Wordpress is 4.9.8 which is fine. So, it is possible that your site is still serving an (old) Wordpress file from a cache.
Please flushed all your caching feature, don't just deactivate it. It is important that you Purge it. Contact your hosting if they have internal caching (memcached or alike) and ask them to flushed it.
Let us know how it goes.