The Torchlight Editor is written in C# and Reflector helps me to look at the functions calls to "core.dll" <- the GameEngine (included in the Editor). The Question is, can you use this functions during Editor-Gameplay? I couldn't find it out, but as long as i see, you use the Editor to manipulate the Scene, then Start InGame and the core.dll loads all manipulations.
My Idea is:
-Take two Editors...connect them together using C# Networking
-Start both Editors using the "INGAME MODE".
-Exchange all required Data using the following "core.dll" functions
EditorConnection.cs (function you call from "core.dll"):
EditorReloadMonsters(...); <- this is important
EditorReloadProp(...); <- this is important
EditorReloadSkill(...); <- this is important
EditorReloadPlayer(...); <- this is important
I forgot to tell ya some Editor CommandLine Options (located in a Manual?):
-adam (don't know what it does)