Hello MManning,
To run the script from the command line you need to use -r command line argument, for example:
photoscan.exe -r script.py
It can be also accompanied by the arguments to be used by the script.
You can get the information about the command line parameters using --help argument.
You can request a 30-day Trial license key for this version via e-mail, by sending a message to support@agisoft.com (just specify, that it should be for 1.3, since the previously issues Trial keys wouldn't fit this version).