Can custom alert files be uploaded to my nuvi 2597?
You might want to look at Getting voice alerts on units without mp3 capability {G} Loading custom alert sounds for POIs {G} Setting alerts with POI Loader {G} Hornbyp's guide to setting alerts with POI Loader {G}
Yes
Can custom alert files be uploaded to my nuvi 2597?
You might want to look at
Getting voice alerts on units without mp3 capability {G}
Loading custom alert sounds for POIs {G}
Setting alerts with POI Loader {G}
Hornbyp's guide to setting alerts with POI Loader {G}