First, minimal test ISO is uploaded for the September 2017 KaOS stable ISO.

provide the installation log, if you encounter any issue at all

As always, early test ISOs are minimal, very few apps, just a web-browser, file manager, text editor, GUI package manager. The non-free nvidia drivers are included since they are a big part of what needs testing.

Biggest change for this ISO is the move to Linux 4.12.8 hardened, this one will need a good amount of testing in Live mode and new installs.
Theming changes include a more custom konsole prompt and a new splash screen.

KaOS ISOs are not only GTK free but are Qt4 & KDE 4 free too.
This is as pure a Qt 5/Plasma 5 ISO as possible.

Plan is to have Frameworks 5.37.0, KDE Applications 17.08.0, Plasma 5.10.5 and Linux 4.12.9 on the final ISO. If all testing goes well expect the final ISO to be released in 10-14 days

Calamares version used is 3.1.1. Release Notes page is not fully updated yet, you will see some the text from the July ISO.

The ISO is using packages from the build repo, but that repo is not enabled, so if you decide to install, make sure to add the build epo to your pacman.conf.

To help with testing:

Use a GPT partition table on BIOS system (manual partitioning)
Use Isowriter to write the test ISO to your USB stick, plan is to remove imagewriter from the repos after this test cycle
Use in live mode on as much different hardware as possible
If you have an UEFI capable system, check if the ISO boots in both UEFI and legacy BIOS mode, make sure though to turn off secure boot
test installs on real hardware are needed, not just vbox
check as many partitioning options as possible in the partitioning of Calamares, see if all works and is clear enough
test with vbox in Live mode and installed and adjust to full screen or resize to different resolutions

debug packages for Calamares are part of all ISOs, run Calamares with gdb if you encounter errors
provide the installation log, if you encounter any issue at all

You can start Calamares from the Welcome app, or run it with:

sudo calamares -d

The install log will be created in the home directory of the Live user, see ~/installation.log. It is available after the install in the target system in /var/log/installation.log
If run from cli, make sure to pastebin the full output, since no installation.log will be copied then, though that log is more complete.

The new site for testing ISOs is still in use:
https://sourceforge.net/projects/kaos-test/files/iso/
https://sourceforge.net/projects/kaos-test/files/iso/KaOS-2017.08.21-x86_64.iso
sha256sum:

8e119cc48222ca476c9a0ab867ae5f579d6d746717de58f22462ebb91504a8a7  KaOS-2017.08.21-x86_64.iso

On this ISO you will find:
Linux 4.12.8
systemd 234
gcc 6.4.0
Qt 5.9.1
Frameworks 5.37.0
Plasma 5.10.4.1
KDE Applications 17.08.0 kf5 based
Git builds of KDE Application that are ported to frameworks, but were not part yet of 17.08
Calamares 3.1.1
Octopi 0.9dev with sysinfo & cachecleaner tool

Known issues:

None at this time