The number for objects in the post 26, for example
26 Ferry
27 Ferry International
42 Marine Boundary (no line)
43 Marine Hazard (no line)
seem to be the decimal codes for Garmin objects - see "cGPSmapper User Manual" at [Only registered and activated users can see links. ], where you can find
26 Ferry
27 Ferry
28 Political Boundary
29 County Boundary
30 International Boundary
31 River
32 Land Contour (thin)
33 Land Contour (medium)
34 Land Contour (thick)
35 Depth Contour (thin)
36 Depth Contour (medium)
37 Depth Contour (thick)
38 Intermittent River
etc.