THe Unlimited Health option in the Trainer doesn't mean you can't die. Some of the Invincible missions in the Capt. Scarlette DLC can result in enough damage to wound and kill. I was lucky enough to get a second wind when killing Hyperius the first time.
That has happened to me even without the No Vehicle Damage option enabled (freezing and crashing). So, it could also be something else entirely.
Even stranger, the one time I did use it, my vehicle continuously smoked as if it was taking continuous damage. I stopped using it.
Steam downloads a lot of stuff that is not BL2 specific, especially Team Fortress if you have it installed.
To be sure BL2 has been updated/patched, you can check the file version of the Borderlands2.exe file (PC location previously posted here). It should be the same version as the Trainer and Editor versions you are using (and listed at the top of the download section here).
firewall and other security software.
on trainer and game.
version and distribution.
• Unlimited Health
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