i got it working also by adding those 2 lines to the custom.conf file.
For reference, I just moved my existing install of PopOS to a temp folder in the root of the ext4 partition and ran the command below, to extract the new distro to the same partition without the need to delete and reformat everything. This process should work going forward to test other releases. if running into a permissions problem transferring the files, do it as sudo and not with chown.
Open a terminal and type sudo tar -xvJpf /home/noob404/Desktop/ps4linux.tar.xz -C /media/noob404/psxitarch and press Enter. Please note that you might have to change the path of the tar.xz archive and the destination drive depending your setup and distro.