Before & after you change the 'FlipFlopWheel' value in Regedit, right-click the 'Device Parameters' folder (the folder that contains the 'FlipFlopWheel' dword) in Regedit & select 'export' & save them as 'Normal Scroll.reg' (Before editing. ie when 'FlipFlopWheel' dword=0) & 'Inverse Scroll.reg' (After editing. ie when 'FlipFlopWheel' dowrd=1) etc respectively.
Then all you have to do is double-click the 'Inverse Scroll.reg' & import it into the registry before playing GTA V & once you're finished playing, do the same with the 'Normal Scroll.reg' to import it into the registry & return the mouse to it's normal scroll direction.
Note: If you install a new mouse you will have to edit the 'Device instance path' (the part like this: VID_17EF&PID_604E\7&16a83a7a&1&0000 etc (it's different for each mouse)) in the '.reg' files, so copy & paste this post somewhere so you can refer to it in future, if you decide to go this route.
The '.reg' files can be opened & edited manually with any text editor (Notepad etc).
Peds vary exactly when they turn their vehicle lights ON/OFF (they don't all do it at the same time) but with these settings above they will switch them on between 19:00 & 20:00 & switch them off between 06:00 & 07:00.
Not sure what controls the headlights being switched on in Rain & Thunder weathers.
Building Night Lights/Windows etc:
Not sure what controls these. In my game they switch on ~20:55 & switch off ~06:55 & the only thing I've found to alter them is the 'Blackout' effect in trainers.
you may have to update both your update.rpf and you can find simple solutions using OPENIV patch OIV installation solutions to get a better result out of your update.rpf being out of date and not being verified properly that way you dont lose out on your mods.