It seems to be a bug in mod/scorm/datamodels/scorm12.lib.php line 61
A wrong key is used to search the usertracks array
The actual condition is :
($usertracks[$setelement]>status == 'completed' || $usertracks[ $element ]>status == 'passed')) {
I think it should be :
($usertracks[$setelement]>status == 'completed' || $usertracks[ $setelement ]>status == 'passed')) {
Valérian