Either export a WAV file from VOCALOID3™ Editor or Tiny VOCALOID3™ Editor and then copy it to your DAW software, or create musical accompaniment data in your DAW as a WAV file and then import it using WAV (STEREO) Track Import in VOCALOID3™ Editor or Tiny VOCALOID3™ Editor.
Also, if you use VOCALOID4 Editor for Cubase with Cubase7 series or later, you can use VOCALOID like a software synthesizer in Cubase.
For more information about VOCALOID4 Editor for Cubase, see the following website:
VOCALOID4 Editor for Cubase
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