I have a laptop and I have absolutely no clue how stuff is connected inside it and whether that might be the root of the problem… (I assume you were referring to desktop PCs only?) 
Anyways, I managed to get Contracts (and SA) working properly. It´s only C47 now that refuses to run properly in HR with AA, which we were discussing in another thread: How to configurate Classic Hitman games on Win10 - #47 by Rimland