am I doing something wrong.
I am not about to test that download;
too many mods are infected with malware,
but a first pass for whether AC lists a track
is whether installed where AC expects to find tracks.
On my PC, that is in Steam\steamapps\common\assettocorsa\content\tracks\
Alternatively, e.g. if installed as a mod using Content Manager,
it might be in Steam\steamapps\common\assettocorsa\mods\
That assettocorsa\ folder may be elsewhere than
in Steam\steamapps\common\.
Since assettocorsa\ also contains AC executables,
one can check properties of a shortcut that launches AC
for the path to that folder.
FWIW, a better (IMO) Mid Ohio mod version folder contains ZWISS.txt.
Older mod versions have rough spots, e.g. in the Carousel.