We only want to use the Java API and don't need a GUI. Is there a minimal installation that removes anything not needed by the command line process? Also can it be packaged as a single directory drop in so that it could be installed when our web server app is built from source control so that developers wouldn't have to install it separably from when they download the project. We develop on window but deploy on Linux so also would like to build directly to the Server and push the Prince app at the same time from source control. How would this be done?

If you're deploying on Linux, then you'll need to install the appropriate Linux package, which does not include a GUI.

Did you ever get a solution to the underlined portion? We have the same requirement.

For the Windows package, you need everything in the Engine folder, which contains the actual formatter and necessary support files.

And would I still have to know the absolute path to the prince executable? Or can I use the prince jar instead somehow to which I would have a relative path?

When you create the Prince object you always need to pass in the absolute path to the Prince executable in Engine\bin\prince.exe.