Welcome to the community. 
- Did you buy this game from Steam? Or is it a “cracked” Steam version, which is not and will not be supported?
- Are you using the alpha/beta/experimental branch of the game, or the public release branch? WeMod only supports public release versions, not test versions.
- Are you using the latest version of the trainer by selecting “History” and making sure the trainer at the top of the list is selected?
- What anti-virus do you use? Some ar more aggressive than others and require additional steps.
- What country are you from? Some have censored western gaming services.
There are no recent similar reports of issues in the official thread for this trainer: Generation Zero Cheats and Trainer for Steam.
This is normal. When a game gets updated, 9 out of 10 times it will break the trainer & it’ll have to be put in the queue for an update. You can see the update queue in the WeMod software. See how it works here: Game Queue
Note that October to January is the busiest time of year for game updates, and therefore also for trainers needing updates. Because of the heavy saturation of public holidays during these months. Halloween, Thanksgiving, Diwali, Christmas, Hannukah, New Year. etc etc.
Have a great weekend in the meantime!