The CSS Plus data is stored in database. You can transfer with export/import tools with other contents. The content link automatically with posts.
Thanks for your feedback.
My plugin works without error.
Please comment the line 185 that contains the function add_action, wp_insert_post.
I want to make sure the problem is fixed before upload the version 1.4.2 with correction.
I not found this problem, yet.
Please, open css-plus.php and replace the line 188 and 192 the variable $post_type_id to $post_id. After, let me know if solved.
Thanks.