Teradata .NET data provider - LEFT() function doesn't work in both V13.x and V14.x of SQL Assistant?

Just wondering why the string function LEFT() doesn't work with the Teradata .NET provider in both versions of SQL Assistant V13.x and v14.x.  It works perfectly well when use ODBC with SQL Assistant the same function.  I had to convert to substr() to make it work for both ODBC and Teradata .NET.  Unfortunately I'm forced to use ODBC at the client side.  Do I need an updated driver?  Is there a fix?
 
Thanks
Chris