1. *IMPORTANT* Ensure that -world=empty is in your launch parameters for Arma 3 so that the "menu screen mission" is the empty ocean scene. *IMPORTANT*
2. Start the mission editor and select Stratis - this will allow the game to load the island without loading the initial Altis menu screen mission and associated units first.
3. Place down a vehicle from the list of 'Armor' class units in the mission editor (Marshall, Panther, Marid or Kamysh), making sure that that the player is a crew member. *IMPORTANT* Make sure the Armored vehicle is the FIRST object you place down in the editor *IMPORTANT*. AFAIK you can place other non-playable units down in the editor afterwards and still trigger the bug.
4. Hit 'Preview' to initialise the mission. After some time the game should send you back to the editor without loading the mission, displaying the message "No entry 'config.bin,CfgSkeletons'."
5. Hit 'Preview' again. This time the mission should load, allowing you to drive your armoured vehicle around, but you will notice that the animations/skeleton of all Man class units in the scene (i.e your vehicle crew) will be broken. This is best observed by dismounting the vehicle and commanding others to do so.