How to import custom post-title link?

I’m not aware of anything in blogger that can provide that link. If I was planning this I think I’d add it as post meta data and generate some kind of MySQL insert statement to add the rows into the DB.

If you want to add a step in php code then the place to do that would be in the class BloggerEntry in Blogger-Entry.php just after this line.

add_post_meta($post_id, 'blogger_internal', $this->old_permalink, true);