Had a lot of POIs files alltogether, and GPS looked crazy . . . sounding 4 or 5 times for the same radar.
How to keep it up todate? Is there anyway so I can upgrade to the latest without loosing the old ones?
Garmin's POI loader has an option to remove custom POI's. You should probably keep a folder of updated POI's, and before senting them to your nuvi, remove the old one's first. Good Luck!
Be aware that if you try to update a single POI file the POL Loader will erase all of the other existing files in that folder. To do it successfully create a folder and copy your existing files (less the one you don't want) and include in that folder your new file. Use the POI loader to upload the "new" set.