Question: what are the exact symptoms that make the car undrivable? Is it only the sensor values, or are there vibrations, or noises, or anything else? Maybe i've overseen something.
As you might know there are a lot of things that can be done wrong when installing a clutch system. Did you triple check everything when installing? Are you shure everthing is 100% centered?
Did you check the flywheel befor installation and compare it with old one? Did you check the clearance angle (Freilaufwinkel) of the old and new one (that's a must).
There also some things you should never do to a new dual flywheel:
https://static.profiteile.de/tmedia/org/006/415_417_SE_VERB_EN.PDF
Some additional infos on dual mass flywheels. Also what symptoms DMF can cause:
https://static.profiteile.de/tmedia/org/006/415_417_600_BR_VERB_EN.PDF
The clutch diameter of all clutches are the same: 240 mm.
The 2.5 and 2.7 do have other dual mass flywheels than the 3.2 engines.
I'm not shure if you can install a 3.2 DMF on a 2.5 engine, because i never tried to.