Difference between Raster and Vector on engraving screen

[ellysgifts]

What is the difference between RASTER and VECTOR on the laser engraving screen? I know that the RASTER does a full left to right action when it engraves, and the VECTOR does more of a line drawing mode.
If I import an image does it matter what the setting is? I am trying to engrave the image of the boat, other than time wise, does it matter which mode I use? Also, my image was imported in the color RED. On the laser screen, red is VECTOR. I have had to change the color of the image to green to get it to a RASTER setting. How would I change RED to be RASTER?

Carolina Cruiser copy.jpg

Thanks,