You can download POI Icons here: http://poi.gps-data-team.com/
or create POI Icons in Paint. Make them 22x22 pixels, and name them EXACTLY as the POI OV2 file name. If you want warnings when you are getting close to one, create another, or the same one, just make it 44x44 pixels AND name it exactly BUT add _X2 to the end of it.