Bitdefender is the first mistake, it can't be fully disabled, it will just turn itself back on. The advanced threat is probably still blocking it. And. even if all scanners do turn off Defender will take over so you need the proper exclusions there as well Also make sure to have the latest framework and .NET core (32 & 64 bit)
Have both latest .NET CORE and FRAMEWORK
(Both of the Net-Core MUST be installed x86 and x64
Extract trainer and make sure trainer/launcher/editor is in a folder excluded from virus scans. Empty quarantine folder if needed or set anything trainer related (paths and EXE's) to ALLOW. Disable any Live/Active/Real-Time tools which may trigger false positives in security software which may terminate the game/trainer when it's activated or options used.
may need to be added to exclusions as well. Run trainer as admin, read the instructions and try again.
Anti-virus help page. Link