Is there a limit to how many threads can be linked back to the Introduction? It was my intention on my latest story to link every thread which comes to a conclusion back to the Introduction so that readers may click on it to start again (I know there's a link right there on the page to do it, but I liked having it as a choice at the end of the chapter). On my most recent conclusion, I couldn't do it; the Introduction would not pop up as an option for a thread to link back to. I know it's possible to have a large number of links to other chapters, because I have one in the story with ten other chapters linking into it, but the Introduction seems to have a limit of four - unless there's something else going on.
No, there should be no limit. (I tested it with 6 chapters linking to the introduction page) Another way would be to add a link at the end of the chapter and not as an option...