From the synopsis at the beginning of this thread...
The Blueprints: Lots of fun information here. Looks like there was a portal system, to this city. Each of the three projects AND patents are mentioned:
Auto Apparatus: Shown on the Blueprint of the Rocket to the Moon building. RTTM was designed to be a "supra-transit" trainer, which would show you your travel status. The figures match up to those in the patent that we found before.
Mark 0: This is the Circarama patent. But, it was actually designed to be a Holographic Virtual Reality projection system. Each of the figures in the patent is explained. Esentially, this could create virtual worlds - like an early Holideck.
Signal Flag: Is actually a portal device. The (T.A.P.E.) deck that was referenced in the patent is the portal controller. Each imaged described is part of the portal grid.