There are 2 types of missions made in this Arma 3. Once you open Editor and make the mission and add some Description and init files they work but doesnt work full. Like DisableAI=true doesnt work on editor preview but if you go to Multiplayer Mission by hosting new on same pc , you can real time edit it there as per Multiplayer mission. So if someone want to test Multiplayer side he needs to create a lan server and create it there. Instead of that , we can change editor to load and save mission like SP and MP . SO everytime we does not need to edit the misison by hosting a lan mission and edit it there.