Since the bug report you link is from May, which KaOS ISO are you referring to? Calamares on the June 27 ISO? That one had all the latest commits from master up to June 25, a new Calamares on a current ISO is not an option, newer will have to wait until a new ISO release, so best to show the full error log and used setup.
https://kaosx.us/docs/
https://kaosx.us/docs/#info-to-provide-for-installation-issues