See my answer below as it will accommodate additional tasks created during the for each item. You're just going to create a workflow and treat it as a catch all so the task won't close until ALL tasks are closed. 

For those that are struggling to remove an action due to "reference in record within the Action Instance File". Here is a link to the Hi article explaining to steps to resolve the issue.  Source: KB0822588 You're welcome! 

So hopefully this will answer some questions. I have the same requirement where I need to wait for all child tasks to close before proceeding. To achieve this in flow designer, you can 'look up the records' and run a 'for each' logic and set a wait f...

Gonna bump this post because I can't seem to set the orientation of the page when generating the PDF. I've examined the plugin and extended it setting the landscape argument to true and it still insists on keeping the PDF in portrait.