I've created a custom post type with several custom fields with the help of WPAlchemy, and now I need to import a bunch of stuff from some CSV files.

I'm using WPALCHEMY_MODE_EXTRACT.

By toying with csv import plugins, I know I can import the fields correctly in the postmeta table, but the problem is that I can't see them in both back and front end.

I managed to isolate the difference between manually inserted posts and imported posts, and it's an extra meta field (_myprefix_meta_fields) that contains serialized stuff I don't know how to generate.

Any suggestion on how to solve the problem and correctly import the data?