Help with HTM please

[rookie]

Hi, I am running a QM macro that calls a standard "Choose a file" window.
I want to paste a file name in it, but nothing works.

I tried:

Key (file name)
Paste (file name from the clipboard)
Ao (ALT O to open a file)
An (ALT N to focus on the file name box)
lef (on the file name box before pasting)
Activating that window (int w="Choose file to upload" "#32770")

The drag utility only sees the window, not the file name text box.
If I stop the macro, I can paste manually.

Any advice so the window takes the QM commands?

Thank you