Yes, adding that rule to your DTL will set MSH:6, assuming the schema you've selected for the target message in your DTL definition uses ReceivingFacility as the fieldname. You can use the numeric representation MSH:6 if you prefer. It will work just as well as MSH:ReceivingFacility, but is not as human-readable.

Looks right to me, @Julian.Matthews7786.

That's a great tip! And for completeness' sake, to use it in a DTL:

The example I provided was nested ... (and tested😉)

And Firefox! Note that the author requests payment equivalent to US$9.99. As far as I can tell, payment doesn't unlock any special features, but it's probably the right thing to do 😁

If Cache isn't running under his account, it likely won't have access to that directory. 

I've never created an IPM module ... it seems like a fair amount of effort to set it up for a single small class and based  on my current status it's unlikely that I'd do it more than this one time.

That said, if some streamlined mechanism for building and publishing it exists, I'll give it a shot ...

Here's an example of the generated query, updated with calls to HICG.GetMsg():
 

SELECT TOP 100 head.ID AsID, 
    {fn RIGHT(%EXTERNAL(head.TimeCreated),999 )} As TimeCreated,
    head.SessionId AsSession, 
    head.Status AsStatus,
    CASE head.IsError WHEN1THEN'Error'ELSE'OK'ENDAsError,
    head.SourceConfigName AsSource,
    head.TargetConfigName As Target,
    head.SourceConfigName, 
    head.TargetConfigName, 
    head.MessageBodyClassName As BodyClassname, 
    head.MessageBodyId As BodyId, 
    EnsLib_HL7.Message.%IDAs Body_ID, 
    HICG.GetMsg(head.MessageBodyId,'PID:3') As Body_PID_PatientID,
    HICG.GetMsg(head.MessageBodyId,'PID:18') As Body_PID_PatientAccountNumber 
    FROM %IGNOREINDEX Ens.MessageHeader.SessionId Ens.MessageHeader head, 
        EnsLib_HL7.Message 
    WHERE (((head.SourceConfigName = 'From_Some_Router'AND head.TargetConfigName = 'To_Some_Operation')) 
        AND head.MessageBodyClassName='EnsLib.HL7.Message'AND head.MessageBodyId=EnsLib_HL7.Message.%ID) 
    ORDERBY head.ID Desc

I just replaced the null values with calls to HICG.GetMsg(). The 2nd argument is the schema-specific path to the values you're extracting, using the same syntax as found in EnsLib.HL7.Message's GetValueAt() method. You can download the class from the HL7 Spy website: https://hl7spy.ca/downloads/HICG_HL7.xml.

There were a couple of solutions mentioned in my reply.

If you need to work with field values in the message, either for routing or transformation, you will need to create a custom schema that includes the Z segment (which you'll also need to create) and assign that Message Schema Category in the inbound interface.

And if you want to transform the message using the DTL Editor, you'll need to specify the custom Message Schema Category for the Source (and possibly Target, if the downstream application needs it) message.

Also, one might be tempted to simply kill the ^Ens.Queue global.

Don't.

^Ens.Queue is used for other housekeeping tasks, and while killing it will absolutely remove all messages from visibility in the queue viewer, it won't change the message headers for those items from queued status to something else (like aborted or discarded). And it will very likely break other things that you really don't want to break.

Here's a short method you can place in a utility class that does what you want:

ClassMethod AbortAll() As%Status
{
    Set tSC = $$$OKSet tQry = ##class(%SQL.Statement).%New()
    Set tSC = tQry.%PrepareClassQuery("Ens.Queue","Enumerate")
    If$$$ISOK(tSC)
    {
        Set tRS = tQry.%Execute()
        While tRS.%Next()
        {
            Set tQueue = tRS.%Get("Name")
            Write !, "Aborting Queue "_tQueue
            Do##class(Ens.Queue).AbortQueue(tQueue)
        }
    }
    Return tSC
}