I had a similar question last year that I asked during a Club Cubase Google Hangout. When you select a VST Instrument from the Rack, the Add Instrument Track dialog opens and you have the option to select an instrument from a general list, or if you click the Browse button, you can drill down to specific instruments and presets by name. Choosing the latter will place the name of the preset/voice onto the track that gets created and will also appear in the Inspector. However, if you choose another preset later on, the track keeps the name of the previous preset/voice that was there before.
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