Regarding your need to trigger two exports at the same time: it is not directly a feature of the API. What I mean is that you can link a single button in your interface with a javascript function that will call requestExport() twice. Since requestExport returns a promise with the exported file, you can wait for both promises to return and do what you need with both files at the same time. Let me know if that is not clear.
Regarding getData(), the function works exactly like all the other getters of the API. You can call it without any arguments to get all of the data from the scene:
api.scene.getData();
or you can use a filter to get specific data outputs, according to their name in Grasshopper:
api.scene.getData({name: "OUTPUT_NAME"});
Thank you for your feedback about the website. We agree overall and we are planning a big update later this year.