I have an old project in which of the three “Spire” one lead is made.
Now I have a new version of Spire (Cubase shows it as “Spire 1.1”) and Cubase shows “!!! Spire !!!” and the channel is empty.
Second example: I used to work with x32 plugins, and now Cubase does not work with this. Therefore, it is the same with many x64 plugins, because they are displayed as “Name x64” and many tracks in old projects are empty, because in old projects this plugin did not have x64 (or x32) written - Cubase does not understand that this is the SAME plugin as the x32 version.