Looks like you don't create loose pages, you must use a section or a chapter (which is fine I think).
However a TOC page will be generated for that section, and as far as I can see you can't change the way it looks for this part only.
For the moment I think I can get away with a Preface type chapter renamed Apropos. My first book pages have stuff like typographical conventions, etc. so I don't mind the added navigation.
But surely I'd like to be able to disengage/customize TOC generation for lighter designs.
One of the loose page I wanted to create is a 1 page "More" page to introduce the whole series of the product to be read after reading this book.
I use the Preface chapter as you said, and this is how it looks:
But then in TOC, this is how it look (yuck!):
And worse - in Portrait mode:
There should be a way to create this 1 page.
Omph. I feel your pain.
On the bright side, you'll notice portrait mode rendering is not that bad. (IMHO) It will look ok once you've added content chapters.
For landscape mode the only way around I can see is having more than one section in the preface chapter. Add copyright, dedication... to your one page and at least the TOC page won't look totally useless.
Or expand the cover page of each book and use a full page for each. Heavy advertising, that. But then it is not like readers are compelled/tricked into going trough the section, as long as they understand its purpose from the titles and chapter cover page.
Perhaps there is another way: convert your one-page into an "Intro media". You could devise a movie quite simply as a keynote animation and export to .mov. The reader would be forced to go through it, but only once in a while.
I don't feel there is any way iBooks Author will offer "loose pages" one day. There is a law somewhere that says a book is made of chapters or sections and only that.
What you are missing I think, is rather the ability to disengage TOC generation for this specific section, and/or the ability to customize its look, section by section.