Main Interface
When DWSIM is opened, you'll see a launcher menu, where you can create a new simulation or open a saved one. If you create a new simulation, you'll get a mostly blank screen with a menu bar at the top and a Log Panel on the bottom part.
The menu bar has commands to control/setup the current simulation, including adding/removing compounds, property packages (thermodynamic models), flowsheet objects and reactions, as well as accessing some tools/utilities, viewing result reports and configuring settings of the current simulation, like system of units and number formatting.