If you installed the apps from sources other than the Play Store, the desktop shortcuts may not be created automatically. To create a shortcut on the desktop, simply click on the All Apps icon (at the bottom of the screen), locate the app, long press on the app icon then drag it to the home screen.

If you installed the apps from Play Store, a shortcut should be created on the desktop automatically. If it doesn't, a reboot of the NextD Player should fix it.