There seems to be a common issue of knoppix-install getting stuck on the partition step, where knx-hdinstall worked fine.
There is a workaround:
For those guys, who just get to the partition menu and can't go to the main menu, as my installer thinks the partition is not yet, right.
Please do the following steps:
sudo rebuildfstab -r -v # this should add all your partitions
export IGNORE_CHECK=1
sudo knoppix-installer
Then you can also install wihtout swap-partition and also install on a disk, which is smaller then we would need it. However do this onyour own risk .

Ubuntu Server 26.04.1 LTS Bootable USB Flash Drive – Latest September 2026
$12.99
Sun Enterprise e450 400mhz cpu(x4), 4gb ram, 9gb HD w/spud most complete on ebay
$500.00
OPNsense pfSense 8-Core Atom C3758 2.2GHz 8GB DDR4 64GB SSD 8x NIC QAT AES VPN
$115.00
OPNsense Firewall VPN QAT 8-Core Atom C3758 2.20GHz 16GB DDR4 128GB SSD 8xNIC
$175.00
1U Rackmount PC Intel Core i5-2520M 8GB RAM 500GB HDD Ubuntu Linux Server
$109.99
Microsoft SQL Server 2019 Enterprise 40 Core Unlimited CAL Retail License FPP
$299.00
All New Ubuntu 26.04 LTS Linux Bootable USB Flash Drive
$15.95
ZimaBoard 2 1664 Home Server 16GB
$350.00
SQL Server 2022 Enterprise 96 Core License & DVD Unlimited CALs with CoA
$284.99
Red Hat Enterprise Linux 5 Server DVD English OS Media Kit RHF0382US
$41.30