I just experienced the same situation; sometimes the camera appears and sometimes not. When you execute the align tool, the camera shows up in the Perspective Setting of the 3D Projection.
Show Model in 3D and go under the menu 3dNavigation Extra/Put a Camera into Path and then go to the floor plan and the camera will be there.
Good Luck. A bit tempermental this funciton.
Rita MF Eng, AIA
iMac 27" 3.5 GHz Intel Core i7
NVIDIA GeForce GTX 780M 4096MB
MAC OSX 10.11.6
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