[GPSNavX]

Yes it is possible to add zooming out further, but here is the issue. Every feature including coast lines has a minimum scale at which it can be displayed. This is in the ENC data. On the NOAA overview cells which get displayed when the zoom scale is set to 1:10,000,000 (Overview) the coast lines and for the most part all features will not display at smaller than say 1:12,000,000. So what would happen is you could zoom out futher, but everything would disappear.

MacENC adheres to the scale minimum attribute of every feature and also the cell scale (i.e. harbor, coastal, overview, etc.). You set the zoom scale in MacENC to see certain scale cells and their respective features.