Hi @jonnilundy, welcome back! 
I'm sorry, I just noticed something. The return statement we have is for the anonymous function passed as a callback to setTimeout. In other words, the anonymous function is returning workflowContext.currentRun.error but the 'errorMessage' block doesn't have a return statement, this is why we see undefined as the data on this block.
Let's make a small change and give it a shot:
Remove return workflowContext.currentRun.error from setTimeout's callback and add it below:
