First of all, a Scribus document should not be created until the text is almost completely finished. Doing big changes (like adding text to existing chapters, changing physical page size etc) can become quite tedious. Scribus also does not do long pieces of text particularly smootly. I tried loading all 350is pages to a single linked frame sequence. It sort of worked, but things got quite laggy quite quickly. Eventually I converged on a layout where every chapter was its own set of linked frames. The text was imported directly from LO files that held one chapter each. The original had just one big LO file, so I had to split it up by hand for the import. If the original had been done with master documents, this would have been simpler.
