Try both #1 and #2 trainers.
Well for me both crashed the system after activating (the voice "trainer activated" comes but then everything kills the game.
It crashing on me sure was not the usual problems. I ran it as admit, antiviris turned off, all that usual stuff.
Try: 2. Watch Dogs Ultimate Trainer (STEAM + UPLAY 10.27.2014).
Not: 1. Watch Dogs Ultimate Trainer (STEAM + UPLAY 1.06.328 CE).
Sorry for the confusion 🤐
[Edited by B4Marc, 2/3/2016 5:12:56 PM]
This worked for me