Same problem. Has anyone made any advancement with this issue?
Perhaps you can use an iframe instead of the traditional menu. So the first frame will load all of you book titles, then you click in the book you want and it loads a different iframe with all of the chapters of the book. Doing this will cut down on file size and memory usage, since only what you’ll need will be loaded.
I have never done this, but a quick google search found a simple plugin that looks like it will do the job.
iframe widget
