Update to 6.21 and Waves Average

I recently updated Igor to v6.21. Unfortunately, doing this seems to have broken several procedures that invoke the fWaveAverage command from the Waves Average package. Has anyone else had this type of issue? The specific error I am getting is: "expected string variable or string function". I have not made any changes to my procedures, or for that matter, any of my experiment files since I updated from 6.12.
Looking at our support database, it seems that a parameter was added to fWaveAverage in Igor Pro 6.20.

// In Igor Pro 6.1x:
Function fWaveAverage(ListOfWaves, ErrorType, ErrorInterval, AveName, ErrorName)

// In Igor Pro 6.2x:
Function fWaveAverage(ListOfWaves, ListOfXWaves, ErrorType, ErrorInterval, AveName, ErrorName)




// Without this comment and the blank lines before it, on Safari at least, this block of Igor code is not displayed correctly.


To make old code work, pass "" for the ListOfXWaves parameter.

Sorry for the trouble.
It took me a while to implement this, because I didn't bother to upgrade Igor. Once I did, I put in this change, which allows the code to work. But it also creates a new issue. It seems that Waves Average will only work if there is a minimum of two waves to average. This is inconvenient for single-run datasets, where there is only one wave. Is there a way around this? My current work around involves creating needless dummy waves, which are polluting my experiment file. Ideally, for this situation the error bars wouldn't be created at all, which is how things worked in Igor Pro 6.12.
I've got a revised version of the procedure you can get by sending email to support@wavemetrics.com.

That version can "average" a single wave once again.

--Jim Prouty
Software Engineer, WaveMetrics, Inc.