If your model has User-defined Attributes that are selected as Model Parameters, you will be prompted to enter initial values for those when you start a simulation run. (You may also change them during simulation via the Change Model Parameters item on the Simulate menu.)
The Model Parameters are displayed in a table. The column under Parameter gives you the name of each User-defined Attribute. The Value column shows the current initial values the attributes will have at the start of the simulation run.
To change the value of a Model Parameter, select it in the table. The Description of the selected parameter will be displayed below the table along with its default value and the mode of its value (Integer, Real, etc.). Then enter the desired new value of the Model Parameter in the Value column. To accept the updated value, press the return or enter keys, tab out of the cell, or click in another cell with your mouse, and the updated value will be validated. If the value entered is not allowable, there will be a warning sound and the previous data will be restored; otherwise, the new value will be stored in the Value column. Important: Clicking any button on the dialog before accepting the changed value by one of the methods described will discard your changed value.
Pressing Reset will cause the selected Model Parameter will return to its default value.
Pressing the Reset All button will set the values of all the Model Parameters back to their defaults.
When finished, pressing the Run button will proceed to run the simulation. Changes will become part of the model and will remain in place if it is saved. (When displayed during a simulation run, this button will be labeled Resume instead, and changes will only be made to the running simulation, not to the underlying model.)