How to change system key function behavior?

[MIRKOSOFT]

Hi!

I'm using emulator and have limited keys to map in its mapping file.
I cannot assign other keys than are not yet used - free are only NumLock, ScrollLock, PrintScreen, Pause.

I associated them to F1, F2, F3, F4 (in emulator).

Problem is its behavior when I press it in emulator
NumLock (F1) - repeats forever F1
ScrollLock (F2) - works correctly
PrintScreen (F3) - in emulator no action, in Windows equals PrintScreen (sends screenshot to clipboard)
Pause (F4) - mapped is as F4, but performs F1 keypress.

Is possible correct their behavior that they will be only pressed keys? That they lost in emulator their Windows function?

I can map also Menu key, SystemRequest, Break, European key left to Z and European key #^
But I don't know scancodes of SysRq, Break and #^
And also there's problem with remapping Break with NumLock.

Thank you for each idea or help.
Miro