You can do it that way (select all), but you first start by starting with the car's BT device, and initiating a contacts "import", then open Petrovich and "send"/"send all".

As far as consolidating "all contacts" into "one file", there are a few different ways.

Easiest, or more commonly used method, is thru "Outlook", export contacts to a *.csv file, then import *.csv file into something like Gmail, which will take that file and add it to its contacts. From there, you can export to a "vCard" (*.vcf) file."