Currently you can only generate documents containing subitems from a specific main item. A more flexible approach is the ability to generate documents that contain subitems spanning multiple items. For example, if the document contains items A, B, and C, it should also be able to include subitems under A, subitems under B, and subitems under C.
I’d love for this to be possible. This way, I could create documents, for exemple, with Chapters (Items) and Paragraphs/Subchapters (Subitems), and still include a lot of text. By creating Forms for my clients, they would be able to include and edit their own texts with virtually no restrictions. I’m eagerly awaiting this implementation. 
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