SCR saves without a save being code (scr code attached)

System OS: Windows 2000, Autocad 2000

I have set up an Autocad Script (SCR) file to insert a raster of a signature that needs to be added to a large volume of drawings as they go out for approval. It works slick and creates the required plt file and closes properly. HOWEVER, there is a .bak file created after the drawing has been accessed and now the raster signature has been saved to the drawing. As you can see from my attached code, the answer to the close dialog is "No" when it ask if I want to save... Does anybody know how to prevent Autocad from saving in this instance.

Stamp Insertion Script

OPEN
C:\e-signature\sass-el-0011_1.dwg
insert
C:\e-signature\E-SIG.dwg
0,0
1
1
0
-PLOT
Yes
Model
Xerox8830
ARCH E1 (30.00 x 42.00 Inches)
Inches
Landscape
No
Extents
Fit
Center
No
..
Yes
No
Yes
sass-el-0011_1.plt
No
Yes
Close
No