Can the PmmC file not be updated on these new ones to turn it into a serial salve device like before so we can still use your library?
For the old screens, keep the PmmC SGC to use the Serial_LCD Library Suite.
For the new screens, unfortunately, the new serial SPE configuration is uncompatible with previous SGC and no serial SGC configuration is provided.
At stated before, 4D Systems provides its own Arduino Library for the new serial SPE configuration.
As a hobbyist, I see limited opportunity to develop my own SPE compatible library as 4D Systems has far more qualified engineers than me!