Vensim 9.0.1 is a maintenance release to fix some issues.
1. New "simulation setup" mode. Click the "Simulation->Simulation control" menu item, or the "Sim Control" button 
. You now have access to all simulation control parameters, plus the sketch is active to change constants/lookups.
2. New reference mode button.
3. Arrow polarity on sketches. You can now change the polarity on arrows quickly.
a. Draw an arrow and immediately press +, -, O, N, U, ? or S, and the last arrow created will use this as the polarity symbol.
b. Select a single arrow and press +, -, O, N, U, ? or S to set the polarity symbol.
4. New model settings dialog.
5. SyntheSim changes. New functionality available when right clicking the mouse on constants.
6. Redesigned SyntheSim sliders.
7. New input/output object settings.
