Gordon, I've upgraded the Hotpot module and now, I can restore a course from Moodle 1.9 with hot potatoes activities, but the first time I click on one activity I get the error message "Source file not found (or empty):/listen/unit10.htm". (I'm using an Oracle database and Moodle 2.2.3+)
Then, I edit the activity, and the HTML file do exist so, when I click on Save button the activity works perfectly.
On the other hand, you were right: I have to upload the media files or images in the same place that the main file is. This solves the problem of the links and images in the title field.
And Stan, I don't create de Hot potatoes activities. Teachers do. And I'm only trying to import the activities from a Moodle 1.9 instalation to a Moodle 2.2. But it is a good advice for teachers. Thanks for your answer.
I was a bit lost ...
Thank you very much for your help