Layout Generator - trace a bmp

I very new to this WM. I have some problem in Layout Generator. I want to create a terrain base on another bmp drawing. This bmp is use as guideline for me to do my polygon in Layout Generator. Can anyone tell me how do I insert this bmp in Layout Generator (for tracing purposes only / guideline for more accurate polygon creation)

TQ

Load that BMP with a loader, add a layout generator, add a combiner, combine them, lock the preview on the combiner, go into layout mode and trace away. This should work.