Custom content doesn't actually use the real %LOCALAPPDATA% but rather what seems to be a hardcoded path using the systems PC Name?
%LOCALAPPDATA% has all the expected save game data etc you'd expect, so it it does use this for save data.
However when we activate custom content and it says that we should add our content to the %LOCALAPPDATA%/Votv/Assets/tv you might not be able to get the assets folder at all.
Instead what the game did, is create a "fake" Appdata using the pc name. In my case it created a new folder path under Users: (PcName)/Appdata/Local/VotV/Assets/tv