I was using the latest trainer for Defense Grid 2 yesterday with no issues on Win 10.
Tonight Windows Antivirus is preventing it from working.
The program loads, it can be activated at the game menu, but the options 1 and 2 do not respond, and Windows notification shows a message, image attached.
I tried turning off setting in the video which had no effect.
Windows no longer gives you the option to allow threats.
for windows defender, you need to add a folder to the exclusions. Link