The create geometry tool within Detect3D and in:Flux can be accessed via the add items tab or by right clicking the Geometry header in the Project Items Tab and selecting Create New Geometry. This will open a new user interface for editing and creating CAD geometry. For step-by-step instructions for building CAD geometry upon an imported image, see the YouTube links below or the CAD Creation Tutorial..
There are 4 tabs on the left panel of create geometry tool which categorize the varying capabilities.
In addition to the CAD Creation Tutorial, please have a look at our YouTube Videos going over building a CAD geometry from an example plot plan. The walk through is in 2 parts and has no audio but provides a detailed explanation of how to go about building CAD models within in:Flux CFD or Detect3D.
CAD Creation Tool - Part 1: https://youtu.be/A5_dGZ8SanI
CAD Creation Tool - Part 2: https://youtu.be/7nRW3iKPwu8