I tried to create a broschure with 16 sites. Open format of one site is 210x210 Closed format is 210x99. I tried a lot but I beleave Indesign accept only to organise the printarea from left to right. But I need a top-down site oranisation.
I hope anyone know the answer.
Thank in advanced
You have to set up your brochure in portrait!
You can rotate the view on screen of your spreads in 90° steps during your work. Only one problem remains, the baseline grid is not rotated, but you can use a frame based baseline grid which can be rotated, you can save this baseline grid in object styles.
Your measures are wrong: Your pages have to have w x h 105mm x 210mm.
99mm x 210mm is the Zick-Zack-fold from a DIN A4 which is 297/3mm x 210mm, this would be wrong here.