Import process tips: import process may require additional server resources, such as bigger memory limit and additional execution time. Otherwise you may meet:
- Error messages
- import process may stop.
In case process was stopped with notices about media failure or incorrect post types - please, try to refresh import page. You will see that every time you refresh, you're getting different messages - that means that your server execution time is less that WordPress importer needed. All you can do - refresh import page several times until you get "SUCCESS" message below importer.