Hello,

​The output of ​​Join activity [ Complete and Incomplete ]  attach to​​ Set Values activity. It will complete/end the workflow.

Also your if activity should have two outputs, one for "Yes" and another for "No". If Checkbox is true ie."Yes​"​​, then it will create a catalog task otherwise it will go to "No" transition​ and skip the task creation for that check box​.

Thanks,

Sagar Pagar