I've just bought XMM and started using it. I've seen a few things that seem sort of illogical or not intuitive, but this might just be because I'm still getting used to it. I've jotted down a few of them and will post them shortly.
One thing that I decided to do since I had a spare hour or two is to re-write the english language file to make it slightly "smoother" to native english speakers. I know english isn't the easiest language to get right so I thought you might have a use for an updated file.
Let me know how to get it to you if you're interested.