Hello again and thank you for your reply.
Right, I think I have it! I was probably overthinking it re the A5 layout. Your suggestion that we use an A3 printer sort of shorted out my lobes and I didn´t immediately see how I could get the most from a page of A4, which many of us are limited to. My fundamental problem was hinging, getting the most I could from one piece of paper and finding a way to do that.
I have in my hands an A5 ´zine´ (taller than it is wide!), the front of which has your ´23 cover in portrait, but when I open and rotate it 90CW, it becomes a flipbook, all printed on my normal A4 max printer, one landscape page after another. And your new layout looks great (way more info for the same ´paper space´! I like it.
For me (Brother L8690CDW), I used page setup-landscape, booklet, (booklet subset)-both sides, binding-left, (orientation)-portrait and ´auto-rotate pages´. I initially printed pages 1 to 8 for test purposes (2 A4) and to limit waste. This may help others.
Kind Regards.
Edit, sorry, an A5 zine