How do you build with a friend

#1 Not without some moderately complex code changes (both C++ and TScript). You'd need to modify the engine so that clients could modify their local terrain object, send those changes to the server for approval/verification, and then have the server pass your changes on to every other client so that everyone could stay in sync. You'd then have to worry about those weird concurrency issues (e.g. situations where some player was modifying the same piece of terrain you were working on).

The guys at WinterLeaf Entertainment are working on a product that might be useful for you. You can do a search for their OneWorld collaborative editor extension for more info.

#2 Thanks for the info I'll go take a look at that now.

#3 Jack:

https://www.winterleafentertainment.com/Products/OneWorld.aspx

By your description, it will do exactly what you are wanting. We are working on an issue that was discovered about 2 weeks ago. It should be completed soon.