My first playthrough was without the map, and let me tell you, I was lost and frustrated for hours. The 2nd playthrough I used the map and got every treasure and never got lost once. If you're getting lost, then you're just not following the map correctly.
the map may have proportions that are not accurate, but it correctly describes the paths and where they are relative to other paths. in actuality many of the distances are probably shorter.. so you'll pass by a lot of paths quickly in certain areas without noticing, if you're trying to measure by the guide map.