Hi,
The similar issue is here with some other VSTis, like Spectrasonics or NI Kontakt. But other plug-ins work as expected. As far as I know, the problem is, that some MIDI files, which are dragged to the Nuendo, contain the Tempo information. This force Nuendo to create a new MIDI track an unfortunately, the MIDI Info data are loaded to the currently selected MIDI track (in a wrong format, so we cannot see them). The wanted data are loaded to the next non-existing MIDI track.