I have tested the trainer options on nightmare mode and managed to get steam achievements with only health, ammo, armor and easy kills turned on. While having these options turned on and after getting my first praetor token, I used the token (not the cheat for the token) and although it did go to 99 after that, dev mode didn't trigger and I was able to upgrade sections of my suit.
I have also successfully used the weapon tokens cheat after getting at least one weapon token in the game, but I turned it off as soon as I was done upgrading my weapons.
Finished the game, deleted the profile, and started a new game, this time with the trainer. I was only using Health and Ammo. Everything was going fine until the...second? level, where I got the secret that gave me the plasma rifle. I got that lovely window telling me the game was in DEV mode and achievements were disabled.
Through windows I went through and manually deleted the ALL of the save game information the game had, all profile information, etc. I'm about to start up another game using the trainer and see where it gets me this time.
I apologise if I got people's hopes up.
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