I have not done the section between marysville and mansfield but if the roads are distinctly marked on that map i would assume they are sealed roads, i would assume that the dirt roads would not show up till you zoom in a lot closer.
As for places to stop, i know healseville have a few nice cafe's, would also assume that mansfield and yea would have as well, let me know how you go and how long it takes, will be buiding a new engine in the next 6 months or so, looks like this would be a great trip to run it in on.