Hi Alona,
Thanks for using our plugins.
We wouldn't recommend you include plugin in theme, the reason is same as Include Meta Box Plugin In Themes/Plugins, you can use TGM Activation Class to tell users that your theme is required that plugin.
But incase you really need to include plugin into your theme, here is the solution. Looks like you've already purchased Meta Box Conditional Logic, so I'll use this plugin and twentyfifteen theme for example:
1. Copy whole plugin directory to your theme, for example twentyfiteen/inc
2. Open your functions.php, add this snippet to the last:
if ( is_admin() )
{
define( 'MBC_URL', get_template_directory_uri() . '/inc/meta-box-conditional-logic/' );
define( 'MBC_DIR', get_template_directory() . '/inc/meta-box-conditional-logic/' );
require MBC_DIR . '/meta-box-conditional-logic.php';
}
Or you can change inc
directory to whatever you want.
Best regards
Tan Nguyen.