To load a Camera from disk into the current project, click the "Load from disk..." button. A standard Windows file dialog will appear. Locate the .PMR or .CAM file on disk, select it and click OK. The chosen Camera file will be loaded into the Project and will appear in the list of Project Cameras. If you choose a .PMR file, the default Camera of that Project is loaded. You can also drag and drop a .cam file into PhotoModeler to add the camera to a project (See Drag and Drop).
Note: once a .CAM file has been loaded into a Project it becomes stored internally in that Project and the .CAM file is no longer associated with the internal copy. The .CAM file on disk can be changed and even deleted and it will not affect the Camera loaded into the Project.