using the installation description at https://blogs.sap.com/2017/09/04/newbies-guide-installing-abap-as-751-sp02-on-linux/ , I managed to get the local installation of NPL in a virtual machine up and running. The underlying OS is OpenSUSE Leap, current version.
I can connect to the SAP system using the SAPGUI of the host machine. However, I cannot logon - no matter if I use client 000 or 001, users SAP*, DDIC, DEVELOPER or BWDEVELOPER, I always get the error message "Name or password is incorrect (repeat logon).
I use Appl1ance as password (even tried copying it to prevent a typo).
During my first try, I even managed to completely lock user 000/SAP* - leading to a complete reinstallation of the system.
The OS is up-to-date, set to english, the root pw is eight characters long with no special characters... I'm out of my wits now.