Note that these are unrelated issues. The trainer will not start at all if related to this issue. You can post in the official trainer threads regarding other issues.
It would show for a millisecond that it was opening but poor nothing, I got it to work by running trainer in Windows 8 compatibility and by not moving the trainer to the game folder. Anyway. Long story short.
Grim dawn trainer
AC Syndicate did not require a fix, something else must be causing your issue. Others titles updated.
Grim Dawn is not affected by this issue. Something else probably updated and is blocking the trainer. Note that only trainers made by Caliber are affected by this issue, so please do not report any trainers by other trainer makers as it is not related. Thanks.
Grim Dawn (Steam Version) was updated today (8/3/2016). Game Version is now 22.214.171.124. That could be reason why Trainer doesn't work for you...
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