For now, I found out, that the sort order is controlled by ShellState key in:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
Default hex value of that key is:
24,00,00,00,33,80,00,00,00,00,00,00,00,00,00,00,00,00,00,00,01,00,00,00,0d,00,00,00,00,00,00,00,00,00,00,00
but that's probably as far as I'm able to go, unless I'll find some more info.