Hello curious aardvark, thanks for responding.
This was apparently a prototype sand/binder printer. It's software is based on Rapix3D which only reads PBM (bitmaps) individually, or a series of PBM files representing each layer organised in a CSV (excel-type file). It has no way of identifying a STL file. Unfortunately there are no "slicer" functions....

The 2.5D printer spreads out a layer of sand, prints the bitmap with a binding fluid, then recoats the next layer over it to print the next layer image. The unprinted sand is removed and remains the printed "3d model".

I'm awaiting response from the creator of this machine, but I feel as though they are avoiding this issue. So I thought of taking matters into my own inexperienced hands.

I haven't found anything via google to answer this need which explains the proliferation among forums (or is it fora?) So it appears I may have to "hack it".

It needs to be automated to an extent, since I will produce several elements (roughly 25), each with around 100 layers. As of now, I can export a single layer onto Illustrator, fill it, then, save as a single bitmap. But I don't know how to make a CSV from an existing PBM (bitmap) and add on to it 99 other bitmaps....