In on-prem Nintex gives you the ability to see the currently running workflow in diagram form, showing each of the actions as it is in the designer, their status and details, you can then click through for more details and errors.
Anybody know why this is not replicated in O365. Only way of coming close to replicating it that I can see, is to write to the history list after each action to mark it complete. If you're not creating tasks, there's no obvious way of understanding where the workflow is up to without this.
I did have a look on Uservoice for this but found nothing.