Create bitmap mask: pick area shape file, and
then the location and file name for it to be saved.
You should probably use the GIF format for most efficient
storage on disk. This will create a bitmap with the
current screen resolution and coverage area, with the
shape file as a solid color.
Load sidescan imagery
Random sampling points: pick the number of points. If there is a
DEM on the map, the points will only occur at locations with valid points on
the grid. The points will be in the current map area.