Zebra ZPL ^A in Zplviewer

Question

Trying to use ZPL code with ZPlViewer. As noted from others it works with simple commands So below simple code should work .But in this example even the command ^A0 fails ?.

^XA^MCA^PR8^XZ

^XA

^DFR:TST.ZPL

^LH110,0

^FO0,60^FS^A0,30,20^FB250,1,0,C,0^FD{0}^FS

^FO5,120^A0,40,3

^XZ

Zplviewer complains about line 5:

zplviewer.ParseException: Encountered "30" at line 5, column 15.
Was expecting one of:
    "^XZ" ...
    <C_MC> ...

etc

Any hints or is the ^A command not supported ?