Q: How to set a shortcut for “Standalone Start” in UPBGE (Uchronia Project Blender Game Engine)?
A: Go to Preferences -> Interface -> Display -> Developer Extras (this makes your life easier). Then go to the “Standalone Start” button and right click it. Select “Assign Shortcut” and choose the key you want to use. Done.
Note: This works in Blender 2.7 (File -> User Preferences) and 2.8 (Edit -> Preferences) only the location has changed. I hope that I could help those who didn’t knew this.