The main menu (1), besides the standard file and editing operations, includes the automatically selected set of tools which are applicable to the current model.

The editor settings (2) allow the user to enable or disable editing features such as snap-to-grid.

The document view (3) presents the current model graphically. It is used for navigating the model and provides scaling (using the mouse wheel) and panning (holding right/middle mouse button and dragging) operations to control the viewport. The same view is also used for the interactive simulation.

Editor tools (4) are used to switch between editing modes, such as creating and deleting the model components (represented by the vertices in the graph with specific semantics, e.g. places and transitions in a PN or gates and latches in a gate-level circuit), as well as connecting the components (e.g. by arcs in a PN or by wires in a gate-level circuit).

The property editor (5) displays the properties of the currently selected component and allows the user to edit them, e.g. to change the label or number of tokens in a PN place, or the type and parameters of a circuit gate.

The component list (6) shows the set of all components supported by current model. A component can be added to the document either by dragging it from the component list and dropping onto the document view, or by using a hotkey, which is optionally specified by the component definition. All components are further assigned numeric hotkeys from '1' to '9', corresponding to their order in component list for faster access.

The utility area (7) has three tabs: the console, which is used to display various information during normal execution of the program and also allows to execute scripts; the problem list displaying errors which might have occurred during execution; and the simulation control panel which is discussed in detail below.

To create a new model, select the New… option from the File menu. A window listing the currently available models (this varies depending on the current plug-in configuration). Choose the required model, and click on OK.

There are two ways to add components to the newly created model. First is to drag (i.e. click and hold the left mouse button) the components from the component list window to the editing area. Another way is to point the mouse cursor to the position where the new component should be put, and press the corresponding hotkey that is displayed in square brackets next to the name of the component in the component list.

To delete a component, first select it either by clicking on it or dragging a selection box around it (achieved by moving the mouse while holding the left button). Then press the Delete key on the keyboard, or click on the Delete button in the editor tools window.

To create a connection, either press c on the keyboard or click on the Connect button in the editor tools window. The editor will switch to the connection mode. In this mode, sequentially click on the first and the second components that should be connected, e.g. a place and then a transition. If such connection is valid (for example, connections between transitions without a place in between are not valid), it will be created and the editor will switch back to the default selection mode.

To remove a connection, click on it (box selection is not applicable to connections), and press Delete.

To change a component's property, such as the number of tokens in a place, or a label, first select the component by clicking on it. Then, in the property editor window, double click on the property that needs to be changed. The property editor will enter editing mode. Type in the new value, and press Enter to accept it.

Start, Step and Stop buttons in the simulation window are used to switch between the simulation and editing modes. When the simulation is started using the Start button, all editing is disabled until the simulation is stopped using the Stop button. After the simulation has been stopped, the system can be reset to the pre-simulation state by using the Reset button.

This mode will periodically fire components that are currently enabled. If several such components exist simultaneously, one of them will be chosen randomly. The interval at which the components are fired is set using the Simulation speed slider. This simulation mode is convenient for large, pipeline-style systems, and helps the user to see how the events propagate through the system.

This mode highlights the components that can be fired at each step. The enabled components are only fired when the user clicks on them (the components with straightforward behaviour, such as consecutive combinational logic blocks in SDFS model, are still fired automatically). This simulation mode is convenient for manual inspection of execution scenarios or for examining the response of the system to certain input stimuli.

This mode allows the user to replay either previously saved traces or the violation traces returned by verification tools. In this way, a sequence of events that leads to an undesired state of the system can be examined by the user, which is very helpful for debugging. If Step-by-step option is selected, only one event at a time is fired when the user presses the Step button.