Acquire legal backup copies of GTA5.exe , GTAVLauncher.exe , and the update folder from a 1.0.877.1 installation. Replace them in your current game directory. Disable automatic updates via the Rockstar Launcher settings.
Rockstar changed the internal addresses of hundreds of natives (e.g., TASK::CLEAR_PED_TASKS ). The Script Hook V update for this version had to manually remap these tables. If you tried to run a 1.0.877.1 script hook on a newer game version, you would immediately crash on launch. script hook v for gta 5 version 1.0.877.1
Most distributions come with dinput8.dll , which is necessary for loading the actual mod files into the game. Acquire legal backup copies of GTA5
Tools like automatically replace your update.rpf and GTA5.exe with the older versions. Always scan these tools with antivirus. Acquire legal backup copies of GTA5.exe