Completion slide doesn't work

Hi there,

I have several storyline projects going into Moodle. Half of them (roughly) correctly report completion via a Pick One slide and Results slide I've set up for the purpose but the other half don't. I've checked, double-checked and triple-checked that i've set up the Pick One and Results slides correctly in all projects, comparing those which are reporting completion with those which aren't and making sure they're set up the same, but still half of them don't report completion.

Can anybody explain what might be happening here? I'm publishing all projects the same and configuring them the same in Moodle.

Is there some sort of global setting in a Storyline project which might be preventing the submission of the interaction? When I click the button on the Pick One slide, it moves to the Results slide without a problem, but the completion isn't being recorded/reported. I can see this both in Moodle tracking and using the Developer Console in Firefox.

All help would be greatly appreciated.

Thanks,

Ewan