When making advanced vehicles and other stuff, that heavily relies on modhooks and unity components, you can never know if it will actually work properly in Multiplayer because of this absolute abyss between Client and Server in Unturned with barely any syncing mechanisms. So we have to test our mods on dedicated servers launched on our PCs to see if it works or not.
Issue is: Before you could just drop the folder with your content into U3DS directory, make sure you have it in your Unturned directory too, and just join and test. Now though, as far as I know, its not possible, and server requires you to add content as Workshop IDs only (at least thats what I’ve been told), and having to make test workshop products, constantly update them when trying different things is very annoying.
Please add some kind of MP compatibility test mode to Unturned singleplayer, where basically it would run both the client and server instances of the game within Unturned app, so that you can see how things would look for a player playing on a server, without having to mess with setting up a U3DS, uploading and updating the test mod continuesly. You wouldn’t have to implement Rocket or other server-related stuff into it, as its only purpose is to test the behavior of in-game content in MP.