SCORM 1.2 is what's supported officially.

However you should be able to manually set it to use SCORM 2004 by first of all making a couple of changes to the code (see https://community.adaptlearning.org/mod/forum/discuss.php?d=204&parent=2058 and https://community.adaptlearning.org/mod/forum/discuss.php?d=332&parent=1575) and second by switching over to SCORM 2004 packaging (the imsmanifest.xml and supporting files)