The attached picture has the offending area marked by the end of my wooden spoon. I can't tell where the leak starts, but it's running down between the frame and the insulation and then onto the ground on the far left side of the washing machine about half way back to the wall.
Looking at the parts diagram, it looks that the offending system may be the Fill and Overfill assembly. Does that sound likely? Which part/s? If so, do I slide the whole beast out from under the counter to access/inspect/repair?