Try this:
--client side
function armyspawn(button,state)
if button == "left" and state == "up" then
triggerServerEvent("movePlayerToPosition",getLocalPlayer(),207.00390625,1865.75390625,13.140625,0,287)
closeWindow()
removecursor()
end
end
--server side
function moveThePlayer(x,y,z,rotation,skin)
if x and y and z and rotation and skin then
spawnPlayer(source,x,y,z,rotation,skin)
setCameraTarget(source,source)
end
end
addEvent("movePlayerToPosition",true)
addEventHandler("movePlayerToPosition",root,moveThePlayer)
As you can see i'm passing "skin" argument to the server side.