HI!Thanks for your reply!
Well, I tried with the iso of 2016.04.13, and calamares fails another time... This time I also tried mounting the target (/) partition with dolphin before the installation, but it fails in the same point: mkfs.ext4 -qF /dev/sda6...
Here is the installation log:
https://goo.gl/TEY6Wm
This bug, in theory, should be solved for a long time. Is it a regression?
I had been able to install Kaos, time ago, with calamares in an extended partion. ( I think with kaos 2016.01)