Thank you, it is nice to answer, but it is not exactly only I seek
By your method, you cannot choose (dwg or others), and i can use (vl-directory-files ...) to look a directory
The solution exists with doslib (function getfilem) and I'm persuaded that it's by the activeX that that is possible.
I'm there almost.
Patience et ténacité m'y feront arriver
@+