Start Visio with Template

[Jumpy]

Hello,
I know it's possible to start Visio with a certain drawing via command line parameters.

But is it possible to start with a template? I can give the path of the template in the command line parameters like I would do with a drawing, and it opens. OK.
But it is opened like a drawing: Not protcted. So if I change sth. and go to "Save" it will save as the *.vst again and possibly smash my template.

Does anyone know how to do this, so that it opens as a template?