ok this alpha for gold pledgers brings in the 3d in test mode editor, which is being released with the beta at the end of this month
. if you have gold pledge you can enjoy this feature now, by testing game and pushing f9.
to place entities in the map after you push f9 push e, have the entities already in the left hand side of editor ready though, if you have not placed at least 1 of each item you want on the map (anywhere out the way is fine) then you wont be able to use them in 3d mode sadly... hope this helps enjoy
have fun stay safe
hood