Changing Distance Alert

The manual setting of poi loader will allow you to get whatever warning you would like. You will need to reload. Don't worry about the old file. It will be over written. Under the manual setting you can set the distance to whatever you would like, listed in feet. I use about a mile and a half.

Yes you will need to run poiloader again using manual mode to re-set the distance.It will overwrite the custom poi files you now have loaded.

Yes, load them again. With POI Loader, use the Manual Mode (rather than Express)--that'll let you set an alert distance of your choice. I use 15000', roughly three miles, and get a visual and audible alert.

You don't have to delete the old file--when you run POI Loader, you new data will overwrite your old file. Note that in its standard use, loading new POIs will overwrite all past POI data, so if you have POIs loaded other than Rest Areas--say, Redlight or Speed Cameras, Dunkin' Donut locations or whatever--they'll disappear as well unless you reload them when you reload the Rest Areas. Yes, you can get around this issue, but without getting into the details, remember that in normal usage, when you run POI Loader to load POI(s) to your Garmin GPS, all old POIs will be gone unless they're part of your new installation.