AutoCAD LT :: Plotting Line Weight Defined By CTB Plot Style

I'm trying to plot a line weight defined by a CTB Plot Style, but the weight will not show in AutoCAD or print.

Here's what I've done;

-Set the line weight in the Plot Style Table Editor, Color 9 @ 0.40mm. Grayscale has been turned on.(All other settings have been left as default)
-Tried various combos like;
-selecting "Display plot styles" & "Plot with Plot Styles" in pg setup
-selecting the "Plot object lineweights". (It also turns off "plot with plot styles" and prints in color (though grayscale is on)
-LWDISPLAY has bee turned on
-Neither model or paper space reflects the change.
-Line types work fine
-Changing the same line thru the Properties Manager does the trick, but I would like to set it up properly thru the Plot Style

Back Ground Info;
-Both the dwg file and Plot Style are new and created from scratch.

If it was a printer issue, it would still show in AutoCAD correctly, right? I've searched various help tools, but seem to be going in circles.