Can't change VSTi in Inspector pane

Cubase
,
1
  1. Load a Cubase 7.5 or earlier project
  2. Select a track with a loaded VSTi
  3. Go to Inspector pane on the left and select a replacement VSTi
  4. You’re being asked whether to close the current VSTi → Confirm
  5. Old VSTi is unloaded
    Result = Can’t load a VSTi anymore.

System specs are as stated in my signature.