You could of course do some scripting like save all unit's type, name, position, direction etc and log it in the .rpt file and then place same units in the editor and copy/paste the 'saved' data from the .rpt
I do these things a bit like that, for placing say hescos and whatnot I use a sort of a 'gravity gun', as in I have simple trigonometry running in a repeated radio trigger for manipulating the objects position (relative to player, usually just x-y only) and another radio trigger for logging the position (into the windows clipboard).
Then it's kinda like a very crude 3D editor.
The 3D editor is in the game still btw, it's just a tad more cumbersome to access, and can't really get why people would use that for what I described above because using it is much more of a chore than the normal 'place unit-preview-adju-preview-adjut-preview...' stuff IMO.