No matter what you do, if you want something to be filled, there has to be a path created for the pen to follow that will fill the shape. The hatch fill is one of the easiest and most efficient ways to do fills. We have written about some other methods here:
To do the hatch fill, you’ll first have to turn the text into paths. Do this by selecting all the text, then do Path=>Object to Path.
Now you can select all the paths, and then do Extensions=>Eggbot=>Hatch fill
Before you do the hatch fill, use Inkscape’s Fill and Stroke dialog box to make Inkscape not fill. The “fill” Inkscape does is not made from any paths, and therefore will not show up in your plot. This is why you have to do the hatch fill…it makes actual paths to do the filling! 8^)
Good luck, and if you have problems then come back here and we’ll see if we can walk you through it.