Latitude 10 problems with Wacom tablet PC drivers

I'm the owner of a Dell Latitude 10 and last Friday, by mistake, instead of installing the v720-10 driver recently released by Wacom, I installed the v720-9 from Asus. As a result, the active stylus stopped working properly: when moving the tip of the pen around the screen, the cursor appears and disappears randomly and never close to the tip. The stylus is now absolutely useless and, because of its erratic behaviour, it is totally impossible to calibrate it.

In order to fix it, I first restored my tablet to an earlier point in time and it didn't fix the problem. Then I got in contact with the Spanish Dell Costumer Service and they first made me install the latest versions of the pen drivers and, seeing that it didn't solve the problem, they eventually sent me a new digitizer in case it was a hardware problem, but this didn't fix the fault.

Afterwards I refreshed the system without affecting my files and, because the problem persisted, I eventually removed everything and reinstalled Windows 8 erasing data thoroughly, but the stylus still doesn't work. The rest of the tablet is OK, even the touch screen is working well.

Now, I don't know what more I can do in order for getting the digitizer repaired. In another forum I've been told that the v720-9 Wacom Tablet PC version ruins the pen sensor on some tablets (Latitude 10 is one of those which may be affected) and that the only fix would be a firmware update from Dell. Can anyone confirm that this is right? Is it possible to fix it?