MHS is a UCE because it is a Cheat Engine that is Undetected. So it is a UCE.
How does it not work for you for vista? I have vista and it works fine. =)
There are a whole bunch of guides ESPECIALLY on the MHS forums on how to get it running for vista. You should look into it if you want to hack. Generally hacking anything nowadays involve Cheat Engines, which is once again, what MHS is.