> motorail vehicles to be loaded and unloaded at Newton Abbot -
> do they go in B1/B2 and, if so, in any particular order?

Yes, B1 or B2, as available.

"In either case, when the passenger section has left the platform the
car-carrying portion will remain. This should be shunted via H2 to the
Motorail unloading bays B1 or B2; unloading will take from 10 to 35
minutes. Once unloaded, stock may be moved to one of the sidings S1 to
S4 if necessary to clear a bay for another train.
Loading of cars may begin not more than one hour before departure; if
you put car-carrying stock in a bay earlier than this, loading will
begin automatically at the appropriate time. Once loaded, you will want
to get the stock ready for attachment to the departing train. This is
easiest done by attaching a shunter to the south end of the stock, and
having it ready in US if available, or in W1 or W2, as the train
arrives. For trains originating at Newton Abbot, it is necessary to put
the passenger portion in the platform first; the two portions may not be
joined in a siding or bay. In all cases the car-carrying vehicles should
be at the rear of the train."

> EX90 - Arrivals at Riverside Yard - do they need to go into RA,
> rather than just roads 1,2, or 3 ?

Yes.

Best wishes,
Tim Bourne (SIAM)