When you have loaded or created a CP-net, and it is successfully syntax checked (i.e. there are no orange or red auras; see Syntax checking), you can start running simulations.
To start a simulation, drag the simulation tools from the index to the workspace.
Now select and apply one of the simulation tools from the tool palette. See Simulation tools for more details on the available simulation tools.
Applying, e.g., the Play tool from the simulation palette will cause the simulation to run a number of steps as specified in the tool cell.
If you have changed or added initial markings on some of the places, you may have to use the Rewind tool to revert the net to the initial state.