OpenEuphoria

You use a program called pw.exe, don't you to handle EUPHORIA programs in some way?

I assumed this was "Phix."

Now, if that is true and you run pw.exe and get that error, it seems to me pw.exe is calling EUPHORIA 3.1 or lower

for it doesn't recognize the namespace command. Thus pw.exe must be modified to run EUPHORIA 4 or it must be fooled into running 4, if that's what you want.