Some blog posts are not imported

I'm importing from an XML file made by Wordpress. Most of it comes through nicely (thank you!) but some posts are skipped.

For those I'm getting an error message like this for each one:

5	Error	count(): Parameter must be an array or an object that implements Countable File /var/www/drupal7/sites/all/modules/wordpress_migrate/wordpress_item.inc, line 784
15	Error	count(): Parameter must be an array or an object that implements Countable File /var/www/drupal7/sites/all/modules/wordpress_migrate/wordpress_item.inc, line 784

Looking at the code, it says:

        if (isset($row->$term_type)) {
          $row_count = count($row->$term_type);
        }

It seems that somehow the $row->$term_type is set but not to a Countable?

I made a small test case XML file and couldn't upload it. I'm now trying it as a text file. Seems to work?

I imported posts as "Blog Post", import categories, do not import comments. Everything else as default.