I have good news for all the XG fans - I just discovered Yamaha Japan has relased an XG Editor for Cubase 4 and Cubase 5 as a VST Midi plugin, and it is very well made. Never been so easy to make an XG Midi with all controls handy! It also come with all the patch names of the latest XG units (like Mu1000, Mu2000, etc.).Check this page
, all the downloads are listed at the bottom.
I tested it with Cubase 5 and MU100r and it worked like a charm.