Lately I have been working on testing new installer images provided by Debian-Ports. I have read that many people tried to install MintPPC with the netinstaller and that it no longer worked. I can confirm this and it is not easy to fix everything.
It requires more work than I thought. Many more programs are no longer available in debian-ports (removed from sid or it cannot be built by buildd) so I have to either compile them myself or chose not to install them. Also other problems and tweaks are necessary. The installation works now, but not everything I want gets installed. I will continue the battle. I will give another update soon. The end result should be similar as how MintPPC looked before but now in a LMDE6 (Faye) environment, which by the way was just officially released. MintPPC will however stay with LXDM and LXDE as Cinnamon is a bridge too far for our old Macs.
Update 4.10.2023
The installer works now. Have a look at the updated installation instructions.