I finally got around to trying Fallout London.
Uninstalled FO4, deleted all the leftovers manually.
Installed FO4.
Downgrader mod didn't work, so I did it manually. One piece at a time.
Installed FOLON. The latest version, 1.01 with the first patch included.
>100GB downloading required on my low quality ADSL line. 1.8 MB/s. On a good day. Not fun times. But it worked.
Awful loading sequence, deliberately flickering and bad in every way as a design choice. Not off to a good start.
Game itself was fine and I really wanted to like it but I was defeated by 3 things;
i) 100+ second loading screens. Over and over and over and over and over again. Want to move from the safe house to the Swan and Mitre to continue the questline? Exit safehouse. 130s loading screen. Fast travel to outside S+M. 75s loading screen. Enter S+M. 65s loading screen. Talk to NPC, leave S+M. 50s loading screen.
ii) CTD, repeatedly. Unhandled exception. Over and over again.
iii) Deliberately annoying level design in which you are very often close to your destination but not allowed to go there, instead having to wind your way through a roundabout route because reasons. It reminds me of the notorious one way system in the city I live in, which was designed and implemented specifically to make it annoying for people to drive into (or anywhere near) the city centre.
A shame.