Here a small update - i couldn't work that much on that project due a lot of work at home... :-/
A normal z80 savekit uses a eprom for the program code and only the z80 will have access... on gorf/wow and every pcb with additional hardware this won't work.
The reason is the additional hardware (e.g. The pattern Board) copies data from the Game-ROM to Screen-Ram. (On WoW or Gorf e.g. the Characters)
This new prototype works with that... (see the pix - don't mind the german language-pack, this is just for memory-map-testing.
BTW: German on Gorf sounds funny, but is unbareable)
yesterday i finished the "Enter Initials"-Program for Gorf (finished WOW already a few Months ago). This was quite heavy and i know now, why there is no savekit for wow or gorf available yet... :-)
Now this week i put the EEprom-Save-Routines and on Weekend Tyrem and I will test it on a Originial Cabinet.
We will send more pix after testing - if everything works fine - the "online-module" will follow

Greetings
Jochen