I've tried to replicate the issue on my test environments, but everything worked without issues. I've tried to add new custom post types while Ajax Search Pro active, and it worked ok unfortunately.
Then I tried to log in to the provided url, but Ajax Search Pro is not installed, so I can't activate it to see if there are any error messages on the CPTUI plugin dashboard. Can you please install and activate the plugin? The account doesn't have permissions to do so, and even if it had, I wouldn't install anything before asking your permission 🙂
If you could also enable debug mode or error reporting in the wp-config.php file, that would help a lot, if there are any error messages. Thanks!Best,
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