[scribus] Splitting a large document into several smaller documents?

[doubtorfear at ruggedinbox.com]

I run Scribus 1.4.2 on a computer with 8 GB of RAM. However, it is 
extremely laggy. It wasn't always this way. The document got slower and 
slower as it got bigger. Right now, the document is around 300 pages 
long, and it takes 5-10 seconds to change just ONE character in the 
document.

It seems clear to me that the lag I experience is a direct result of the 
length of the document. Because the document consists of one very long 
linked text frame, it has been suggested that those linked frames are 
the cause of the problem and that I may be able to fix it by splitting 
the document up into smaller chunks.

The problem is that I've already invested a lot of time into this 
project. Is there a way I can split the document up easily without 
typesetting everything from scratch? One suggestion was to make multiple 
copies of the document and delete all unwanted pages from each copy to 
form the desired chunks. However, I found that deleting pages doesn't 
affect the text of the document. When I delete a page, the text frame on 
that page remains and simply gets placed on the page that gets moved 
down to take the place of the deleted plage.

Please help!