Looked into the ignition switch possibility a bit more today. The switch is very similar to the 9000. Metal fixing plate is different of course - the 9000 one costs much less - and terminals C and C1 are missing. I think these connect to the auto box switch on the 9000.
Anyway, just inserting the key, pushes a small nylon post that makes a connection between 30 (12v +) and the B terminal, then 1st position connects 30 to X, 2nd position connects 30 to 15 and 54. Starting connects 30 to 50, which is the relay for the starter motor.
The B terminal only appears to supply power to the DICE and TWICE units. X terminal supplies headlights. 15 supplies ABS, MIU and airbags. 54 supplies cruise, window lifts, indicators. (these are not the full list of components for X, 15 and 54, but you get the idea)
In view of the above, a strong suspect for a poor contact is B. I am guessing that the car would not start if there was no voltage to the DICE or TWICE. If another set of contacts failed, then other components would not be working and a check could be made.
PS the terminals referred to are actually marked on the ignition switch and shown in circuit diagrams.