James, you beat me half an hour, and you are spot on! 
I was just about to post the same thing.
Air-cutting the file produed the anamolous moves to X0Y0Z0 that seem to be caused by the XnanYnanZnan lines, of which there are 16. Removing the lines eliminated the anamolous moves.
@Steve, I see you have arc fitting enabled. Look at your Carbide3D-MM.con in the posts folder and see if the formatting lines for arc moves (the bolded lines below) are commented out (with leading semicolons). Edit: I have fixed the copy below by removing the offending semicolons:
; MeshCAM config
; This config is the Carbide3D Nomad 883
; http://www.carbide3d.com
;
DESCRIPTION = “Carbide3D-MM(*.nc)”
FILE_EXTENSION = “nc”
UNITS=MM
;Feeds
FORMAT = [F|#|F|1.1]
;Moves
FORMAT = [I|@|I|1.3]
FORMAT = [J|@|J|1.3]
FORMAT = [X|#|X|1.3]
FORMAT = [Y|#|Y|1.3]
FORMAT = [Z|#|Z|1.3]
FORMAT = [R|#|A|1.3]
;
;
COMMENT_START = “(”
COMMENT_END = “)”
;
START = “%”
START = “(FILENAME: [FILENAME])”
;;the following sets the stock for CutViewer
START = “([CUTVIEWERSTOCK])”
START = “G21”
START = “G90”
;
TOOLCHANGE = “([CUTVIEWERTOOL])”
TOOLCHANGE = “M6 [T]”
TOOLCHANGE = “M3 [S]”
;
RAPID_RATE_MOVE = “G0[Y][Z]”
;
FIRST_FEED_RATE_MOVE = “G1[R][Y][Z][F]”
FEED_RATE_MOVE = “[R][Y][Z]”
;
FIRST_CW_ARC_MOVE = “G2[X][Y][I][J][F]”
CW_ARC_MOVE = “G2[X][Y][I][J]”
;
FIRST_CCW_ARC_MOVE = “G3[X][Y][I][J][F]”
CCW_ARC_MOVE = “G3[X][Y][I][J]”
;
;
END = “M5”
END = “M30”
END = “(END)”
END = “(OF PROGRAM)”
If so, uncomment them as per above. They were commented out in my copy of the MM post, but not the inch post… That is a possible source of the anamolous lines.