Today I managed to repartition N9
My partition table looks like that:
p1 - MyDocs, 4,9 GB
p4 - extented, 3,9 GB
p5 - Nemo, 1,46 GB
p6 - Sailfish, 1,46 GB
p7 - Leste/Devuan (for testing), 1 GB
p2 - Harmattan, 4 GB
p3 - /home, 2 GB

I used Ubiboot maintance mode, and repartitioned with GParted (resizing), parted (restoring rootfs) and Harmattan's mkfs.ext4 (formatting)