I don't own a full version of Melodyne and would probably never use it with Music Maker, but I just tried the demo in my Music Maker 14 PE and it works fine as far as I can see. The plug-in loads up properly and does what it's supposed to do. Both plug-in and host seem to run stable when using it.
Naturally, this wasn't really an extensive test, but so far so good. You should also try the Melodyne demo in your Music Maker. VST is generally a pretty solid standard, but some VST developers optimize their plug-ins for specific hosts. While the page above doesn't seem to give a lot of hope for Magix audio products, they do list Samplitude on their official compatibility list: