Hello Russel, I suggest to set it to block level as a first one. Next question is how do you test the bookmarking? By using Preview? You need to "simulate" an LMS connection or upload in an LMS or use Scorm cloud.

I used to publish my module, open the imsmanifest file, start the module, close and reopen to test it on my own computer, you do need to have some webserver running for that.

what are the steps to see it working thanks.

Either publish the course and upload it to an LMS - or preview it but then add scorm_test_harness.html to the end of the preview URL (this will make the course think it's on an LMS but actually the data is just being stored in a cookie)