Hi,
problem (almost) solved
Thanks to your help and suggestions, I finally rememberd that I had similar problem of “strange” resolution with X-Plane. And actually the reason was the same. Being my eyesight not perfect, in Windows I set a customised DPI size of 150%, to have a bigger system text dimension. This seems influencing some games/sims, and requires that in the Properties panel of the program I must, in the Compatiblity tab, disable the screen resizing for high DPI.
I just tried this with the BMS executable, and actually it had effect. The strange thing is that now the 2d windows (menus and various pages) are quite small (about half of my monitor resolution), but still readable, but when the program goes in 3d (for flying) now it is in effective full screen at full resolution, and in the second monitor I actually see the extracted elements (MFDs, DED) with the expected sizes and positions.
So thanks a lot for the help, I can stand with the smaller 2d windows, the important thing is the full 3d screen and the secondary cockpit elements.
One last question, considering that I am completely new to the whole issue of cockpit extraction: is it not possible to also extract the OSB buttons of the MFDs, right? Do they eventually require some dedicated hardware panels? In practice on the second monitor one can visualize the MFD information, but for operating the relative buttons is it always necessary to directly working in the cockpit?