Code:
zoom
e
erase
1,1
0,0
-insert
filename
0,0
1
0
explode
l
close
n
Zoom extents to ensure your object is visible (not strictly necessary but some graphics cards might cause a problem without this).
Erase - substitute two x,y values that will form a crossing window over your object(s) but nothing else - higher x-value in the first line.
Insert (without a dialogue box) the file containing your incoming objects at 0,0 with 0 degrees rotation.
Explode Last.
Close file and confirm save.
Note that the blank lines are important (except at the bottom of the code above) and there must be an [enter] at the end of the last line (the "n").
Use Notepad to create the script file. Save it with the extension .scr - you must have already unchecked "Hide extensions for known file types" in Windows Explorer's or My_Computer's "\Tools\Folder Options\View".
The new file name must not already exist as a block name in the working drawings.
This assumes that the working drawings, the new file and the script file are all in the same directory.
This will work on the one open file at a time. To fully automate it you could use a batch file but it's been too long since I did that so I'll leave that to someone else.
Have fun.