Correct me if I am wrong, but as far as i know Scribus is more for layouting purposes and print media. I am not familiar with its handling to be honest, years ago I head a quick glance at it.
What if we used the open document format Ascension chosed by himself? Once the basics are set one can use word or open office or any equivalent being able to save in odc.
The results can be exportet easily into pdf, and therefore viewed on any system including those nice features as 'jump to...' by clicking chapters in the index.

>Moe