Damian Baker

Hello Takahiro,

Thanks for your message.
No it should work fine with WordPress 3.9.1 as I have tested it with this version of WordPress. This is a strange issue, that seems like it could be a PHP memory error (without outputting the error).

Please provide us with temporary admin login details of your website via our email address: support@css-javascript-toolbox.com and we will take a look for you.

Also, are you running the latest CJT Dev 7.1 version?

Kind Regards,