There is an issue with GTA V ReShade + ENB combination. ReShade 4.2.1 works fine with it + ENB on Windows 10 1809, but not Windows 10 1607. Windows 10 1607 only works with ReShade + ENB if ReShade version 2.0.3... Why would ReShade + ENB act differently on Windows 10 1607 and Windows 10 1809? The only related difference I know of is that Windows 1607 does not support what is known as "Fullscreen Exclusive Mode Optimization" (FSE), while Windows 1809 does support FSE.
Installed ReShade. 1.1.0 with SweetFX 2.0. Was actually able to get into a game and play half a round, however it crashed straight to desktop after 5 minutes. Didn't hang, no error message. It's progress at least.