Max,
The S/O sim training used to be exactly the same as the F/O course without as you say the dual engine failure and the RNAV. Personally I think the S/O sims are more difficult that the FO setup. Once you have done a few RT/PC's you realise that it is pretty much the same thing over and over again. The dual engine failures are always flown by the commander (as would be the case in reality) so after that initial course you won't fly one again until your command.
S/O modules, although scripted, are often changed extensively by the instructor to suit your experience and can be very challenging when you consider that you don't get a chance to practise on the line.
The S/O job is a doddle but the sim training
/checking is not!
W2