External processing is use to load a file from other systems and process the file.
The Pairing auto roster saves an image file in the database after each run. This mean that you can make several runs and when you have the best solution you can load the "external" file.
You need to build a template to type "External Processing".
The solution is still under development which mean that you have to select a "Include input data from template"
but currently it doesn't matter which one you select.
and you should only use "Read rostering solution from past runs".
From the drop down list you can select the past runs.
To run the External file, open AutoRostering, make sure that the period and the Human Resorurce is the same as in the External file.
In the rostering part select the "external file".
Click Process and after few seconds you can load the result to the gantt.