using the just downloaded release of the questionnaire for Moodle 1.9
I made a course backup.
Inside the course they are only a present: the argument 0 summary, the news forum and a questionnaire.
During the restore process I got the following error:

Notice: Undefined index: 0 in bla/bla/bla/moodle19/mod/questionnaire/restorelib.php on line 324

In the questionnaire I have 118 remote user record and this error message was shown 416 times.
Privately I am even available to share the course backup.

By the way, even with this notice, the restore process was successful and the questionnaire was correctly restored.