Hi all, 
I'm a newby in Salesforce so I decided to start learning with the Trailhead. 
I have completed all the challanghes related to the "Getting Started with the Force.com Platform". 
This morning I started with the part 2: "Intro to Visual App Development". 

The fist challenge for Workflow Atuomation is about "Automated Process with Workflow". 
I did the challenge but I receive a failure even if It should seems to run correctly in my Develper Edition Platform. 
Tha error massage received by the check challange button is "Challenge not yet complete... here's what's wrong: Case escalation failed to assign a task to the owner."

I say that all seems to work fine because I edited e case, set up the Priority to High and: 
1) The Escaleted flag was set automatically to true as per the rule action defined
2) I receive a notification about escalation on that case (because I'm the owner of the case as per the task definition field)
3) An activity under the case was automatically created and assigne to me. 

As anyone tha same problem?
Any help would be much appreciated. 
Thank's in advance,
Alvaro. 

I continue getting an error on the Workflow Rule in the Trailhead excercise that says a workflow field update action was not found, but I have created it.  

Challenge not yet complete... here's what's wrong: 
The 'Set Case to Escalated' Workflow field update action was not found.
Create a workflow rule that will update a field.In some instances, a case must automatically escalate. Create a workflow rule that will set the escalated flag and send a task to the case owner, if a case is not closed and its priority is set to High.

Can someone please help me with this? What is the correct formula for the workflow itself? Perhaps the error is in my current formula.
Thanks!