Hi Andrew,

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.

http://www.celemony.com/cms/index.php?id=demo_plugin

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:

http://www.celemony.com/cms/index.php?id=plugin_comp

That doesn't say anything about Music Maker of course, which is a completely different product family, but long story short: it seems to work for me.