"Although Amstrad CPC is not the preferred choice among vintage computer fans....." ???
Even though the above opening statement doesn't inspire confidence, the blog is actually worth checking out.
https://swarmik.tumblr.com/post/174909514784/playing-colossus-chess-on-amstrad-cpc-6128 (https://swarmik.tumblr.com/post/174909514784/playing-colossus-chess-on-amstrad-cpc-6128)