There has been a new User Manual for over 4 months. You can get the new User Manual when you install the new version of the software. Download and install the latest release of StormNET. Then, select Help | User Manual.
StormNET Downloads, STORMNET Software, stormnet tutorials, and stormnet documentation
There also have been many new features added to StormNET:
Urban Drainage Stormwater Sewer Software