I tried to download the Concentration audio game but I get a message that says, "Can't reach this page."
for now please visit https://www.agarchive.net/pages/devs/kitchensinc.html to download the games.
it seems the archived copy of Jim Kitchin's site with all his downloads seems to have gone wrong.
i can fix the page and download links from the audiogames archive but that will be quite a time consuming task and there's only one of me.
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)