As you can see on github mentioned demos for .net were were updated about a year ago. So it could be just outdated.
You can try to find more recent source code of demo apps inside of installed Link Os SDK.
1) press Start button
2) Find SDK in menus: All Programs -> Zebra Technologies -> Link-OS Multiplatform SDK -> Link-OS Multiplatform SDK. It will open file explorer in the root directory of SDK.
3) Go to subdirectories: pc-.net -> v.2.15.2634 -> demos
4) Find there a demo you needed.
Software Engineer, Kutir Mobility
Posted on behalf of Zebra Technologies