[mkgmap-dev] Display of railways

Another Garmin foible... Sightly off-topic, but I thought this was the best place to post this information. I have a Streetpilot c550 and an etrex Legend HCx. On both, the last zoom setting at which railways are visible is 800ft (resolution 23) with normal detail setting. I have discovered that the receivers override the resolution which is set in the map (usually around 18). Why have Garmin done this? Does someone at Garmin not like railways? RoadTrip does respect the resolution which is set in the map. I have worked around this by changing the line type used for railways. I make the new line type look like a railway, with a .TYP file. I use type 0x10 in a non-routable map, and this works as expected.