Intevation is developing a specification for GREAT-ER 2: Read the Vision.
You can have a look on some screenshots of GREAT-ER 1.0.
Links: CEFIC (there you can read more about the Long-range Research Initiative of which GREAT-ER 2 is part of) ECETOC (there you can get in contact for the software GREAT-ER 1.0)