To fix the issue with multiple FabStation Apps opened at the same time on the HoloLens, please: 

1. Open HoloLens Settings on the home page.
2. Go to System. 
3. Click on Holograms.
4. Turn On the toggle for  “Automatically remove all holograms in mixed reality hone when device shuts down”.

With this setting on, every time you turn off the device, it should shut down all apps including FabStation