You would think that XFAB's PDK would have basic info on setup
for MC analysis, where it diverges from "Spectre out-of-the-box".
To that, you want the Cadence docs. I haven't run MC analyses
since IC5 days, so....
You might see if XFAB contact channels can get you to a CAD
applications engineer who has a 2-page howto in pocket.