It is always better to open a MIDI file. For many good reasons.
And if you go to preferences/ midi devices and choose
none as the output, opening any midi file will automatically set sonar up with the TTS_1 so you can listen to the file the way it was originally composed.
You'll have a nicely set up project ready to edit by adding and swapping out better sounding VST instruments.
If you still have 8.5 installed Artist will use it's VST's so nothing will change for you that way.
Basically the different versions just come with more VST's and plug ins.