Dear Scott. If the 2.5 and 4.5 curves worked for you in the past, they will still work for you now. Those old curves are still here: https://inkjetmall.com/blog/blog/piezography2-digital-negative-and-print-system/
And we still sell the 2.5 and 4.5 on our website.
We do not “officially” support the 2100 any more but it may work with our new PiezoDN curves for the epson 2880. PiezoDN allows for full calibration of the negative and is a paid software $75.00 that gives access to a private support forum as well.