Thanks for replies.
DOSBox create a file when done loading (in autoexec) and then have a file/directory monitor on the host.
Yes, this is the first choice I've thought and done.
The external script (AutoIt) runs dosbox.exe and the last command under "[Autoxec]" section (dosbox.conf) copy an empty file ("db_ok.tx1") with another name ("db_ok.txt").
When the function "FileExist" of the script notes that new file, starts the other windows programs that I need and delete the file used for the check before exit.
So all is ready for the next restart of dosbox.
I hoped for something more simple, but it is not a big problem.
The procedure is a bit complicated, but works fine.😀
It's a generic prompt after the "mount" in "[Autoxec]" section of the configuration file, just for understand the conditions, could be other of course.