Hi, sure thing.
Im hosting a mp game, I want ther other players to play using my ships (there are a few reasons why in competition, the organisers need the ships b4 the game, Constant ship loadouts in a tournament/ honesty issues between games changing ships. There are others. If you want ill go more in depth.)
The ships I want them to use are in my ships folder.
I click the 'check list' style button located at the bottom of the mp setup screen with all the other on/off settings. The text next to the little box is "Host Issues Ships"
Once the box is 'checked' the players no longer can fill their own ship slots, the host can fill everyones.