Abbreviation: 
Turtle in the toolbar.
You can let run the virtual time of the simulated machine slowlier or faster. By this you can analyse critical moments calmly while you let processes which run already correctly pass quickly. The precision of the simulation is not influenced by the slow motion or the quick motion, the simulation repetition rate keeps always to the value which is adjusted in View|Options|Simulation.
You can also change the simulation speed with the Speed-Trigger automatically.