I do confirm that a real
purchased version of Navigon works for hours without disconnections.
In fact, there's normally an upgrade deal available from Navigon if you already own some other software and are willing to send it to them physically to Germany. I've snatched the upgrade deal from AA Navigator, and it was just €79 (£53 by the time of purchase).
buy the memory card option though -- the card included is just measly 128MB and you get it for €50 extra price tag, so this is perfectly unneeded thing - instead you can buy a 512MB card elsewhere for the same money
Convenience reason also fails here -- You will still have to download the map upgrade from the Web and put it on this card manually.
P.S. to the author of the original question: I don't think the problem lies within Navigon itself ;) because with keygen, there's no way it could detect how the code it was generated, I don't think there are two keygens possible that will fit the checking algorithm -- it's highly sophisticated and involves the device ID.
O2 XDA Exec
Now: Midget ROM 1.0, 2.20
Was -1: JWright's Radio 1.15.00, ROM 2.02.02 WWE, 09/04/2007, Protocol Version 42.51.P8, BootLoader 1.01
Was -2: Bog Standard Radio 1.09.00, ROM 1.30.107 WWE, ExtROM 1.30.162 WWE, Protocol Version 42.42.P8, Bootloader 1.00