[Plugin: Content Types] WP_Query and custom fields?

Is there a way to specify custom content type fields in the arguments passed to WP_Query() aka query_posts()? E.g:

$args = array( ‘post_type’ => ‘asset’, ‘posts_per_page’ => -1 );
$loop = new WP_Query( $args );
etc.

I’d like to be able to use custom fields in WHERE and ORDER BY clauses without writing custom SQL directly. Thanks!

http://ww.wp.xz.cn/extend/plugins/content-types-wordpress-plugin/