Sorry for the late reply. Only just seen your PM.
For 7 digit Search you need 268X firmware or higher AND V7 or higher maps. It's not one or the other.
268X, 272X, 276X, 280X, 281X, 380X and 381X firmware should all work on that unit. (I just put the X as the last digit changes depending on the make of car. So for example VW is 2680 Skoda is 2684 but it's the same firmware loaded from the same disc.) If it stops again and the unit hasn't bricked (shouldn't happen unless it stops during the CAN Gateway upgrade) i would suggest re burning the Firmware onto a Branded DVD +R (Verbatim are the best bet) at the slowest possible speed. I have seen some units just be fussy over CD & DVD.