As well as the rear cab, the 230s could be worked from the door in the centre of the train in each carriage. There was no PA installed however for the station to be announced when "Doris" was not working.
The TVMs do not accept cash, so anybody without a smart mobile would be unable to buy a ticket, except from the guard. Incidentally, I was told the cost of each TVM was costed at £60,000 fitted each. Ouch!
I have seen quite a few times for passengers that have been stranded on the "wrong side" of the crossing, the guard has waited for the barriers to be raised whilst the passenger ran across for the train. The only exception, perhaps would be at a crossing point and one train was on time and one train late where the barriers were not raised.