Hey! Plugin has been updated v1.1.0, probably the bug you reported should be solved now.
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Take a look on the post Iwritten for the update :)
You Will find a parameter config for the Visustella MenuCore
I have added a Better compatibility with VisuStella MenuCore, allowing developers to add the command through the parametera of the menu core. So, when Visu Menù Core Is in the project, the "Show In Menù" parameters Will Just be used as a flag.