Hi Sam
The setting New window (simple) gives complete control to the SCORM package, and the SCORM menu is not displayed in Totara. When using New window the SCORM menu is displayed as some control is retained by Totara.
Is there an extra menu item that isn't selected such as Start new attempt or to close the SCORM when new window (simple) is chosen?
There is some information on the settings for handling of multiple attempts Are you able to check the value of cmi.core.lesson_status is completed', 'passed' or 'failed' - this can be done through the SCORM report and checking the attempt .
Regards