Nintex Newbie

Workflow doesn't start with library enabled check out/in

We have a site collection reusable workflow that works as expected if check in/out is NOT enabled on the document library.  Unfortunately we need to enable check in/out on this library.

Now when we try to start the workflow, it pauses, then stops (no errors).  The workflow history doesn't show the workflow as having started.  The document is then shown as checked out in the view.

Are there some restrictions on running certain workflows with check in/out enabled?  Any additional steps/actions that need to be included?  We are using Nintex Worfkflow & Forms 2016 on-prem.

Thank you in advance for any suggestions/advise.