I'm simulating an oscillator circuit with Ultrasim, when I set what I believe to be the default accuracy in Analog Design Environment by going through Simulations -> Options -> Analog and change the Simulation Mode from the default Mixed Signal (MS, 5) to Analog (A,5), the oscillator oscillates.
 
However, if I change the sim_mode and speed in Config to the same exact settings, i.e. "a" and "5", the oscillator does not oscillate.  In fact, changing the sim_mode and speed in hiearchy editor seems to have no impact on the accuracy of the simulation.  I used the Ultrasim template when I created the Config view.