Well I guess that's a problem of the unity engine. Unity is total cross platform engine and I believe so are the tools of this engine. Sadly.
For example I also play Verdun which is also using the unity engine. I still can remeber the first ...lets say up to ten versions of the game. One bug was fixed, next one appears and so on. The most annoying thing back then was stuttering in some versions. Developers were/ are really friendly and open minded concerning the rants from the community and so they really worked hard to fix all issues.
Today it is really stable and enjoyable but it took about two years to finally get there.
I don't think it has anything to do with the Game/Tools being based on the Unity Engine, bacause the game is generally bug-free (at least in the singleplayer) and plays very smoothly.
I'm 99% sure that the Editor Package was made in haste and not tested at all, what is really sad. They just need to get their devs make some elaborate maps with the Package themselves, and repair the bugs that appear during the process.
The Editing Package is not the same thing they used to make the game. The assets are not exacly like the assets in the game. Working with the Editor Package is like making a framework/recipe for the game to interpret and build a proper map with proper game assets. At least that is what i understood from the Guide.