Disable Windows Key

You could use windows hooks, heres an example using a low-level keyboard hook that disables the left WIN key and the right WIN key as long as the hook is active.

see Windows Hooks for more info.

hook.c

#include <windows.h>

#define EXPORT __declspec(dllexport)

static HHOOK current_hook;

EXPORT DWORD keyboard_hook( int ncode, WORD wparam, KBDLLHOOKSTRUCT *lparam) {
	if( ncode < 0 || ncode != HC_ACTION) return CallNextHookEx( current_hook, ncode, wparam, (DWORD)lparam);
	if( wparam == WM_KEYDOWN || wparam == WM_SYSKEYDOWN || wparam == WM_KEYUP || wparam == WM_SYSKEYUP) {
		switch( lparam->vkCode) {
			// keys to disable
			case VK_LWIN:
			case VK_RWIN:
				CallNextHookEx( current_hook, ncode, wparam, (DWORD)lparam);
				return 1;
		}
	}
	return CallNextHookEx( current_hook, ncode, wparam, (DWORD)lparam);
}

EXPORT int init_hook( HHOOK hook) {
	if(hook) {
		current_hook = hook;
		return TRUE;
	}
	return FALSE;
}

Compile dll:

gcc -shared hook.c -o hook.dll

Hook.bmx

SuperStrict

Const WH_MIN:Int = -1
Const WH_MSGFILTER:Int = -1
Const WH_JOURNALRECORD:Int = 0
Const WH_JOURNALPLAYBACK:Int = 1
Const WH_KEYBOARD:Int = 2
Const WH_GETMESSAGE:Int = 3
Const WH_CALLWNDPROC:Int = 4
Const WH_CBT:Int = 5
Const WH_SYSMSGFILTER:Int = 6
Const WH_MOUSE:Int = 7
Const WH_HARDWARE:Int = 8
Const WH_DEBUG:Int = 9
Const WH_SHELL:Int = 10
Const WH_FOREGROUNDIDLE:Int = 11
Const WH_CALLWNDPROCRET:Int = 12
Const WH_KEYBOARD_LL:Int = 13
Const WH_MOUSE_LL:Int = 14
Const WH_MAX:Int = 14
Const WH_MINHOOK:Int = WH_MIN
Const WH_MAXHOOK:Int = WH_MAX

Const INIT_HOOK_NAME:String = "init_hook"

Global IsHookLoaded:Int
Global IsHooked:Int

Private
	Global Handle:Int
	Global InitHookProc:Int( hook:Int)
	Global HookProc:Byte Ptr
	Global CurrentHook:Int
	
	Extern "Win32"
		Function LoadLibrary:Int( name$z) = "LoadLibraryA@4"
		Function GetProcAddress:Byte Ptr( handle:Int, name$z)
		Function FreeLibrary:Int( handle:Int)
		Function SetWindowsHookEx:Int( hooktype:Int, hookproc:Byte Ptr, handle:Int, param:Int) = "SetWindowsHookExA@16"
		Function UnhookWindowsHookEx:Int( hook:Int)
	EndExtern
	
	Function on_end_hook()
		FreeHook()
	EndFunction
	
	OnEnd on_end_hook
Public

Function LoadHook:Int( hookdll:String)
	FreeHook()
	Handle = LoadLibrary( hookdll)
	If Handle = 0 Then Return False
	InitHookProc = GetProcAddress( Handle, INIT_HOOK_NAME)		
	If Not InitHookProc Then
		FreeLibrary( Handle)
		Return False
	EndIf
	IsHookLoaded = True
	Return True
EndFunction

Function InitHook:Int( hooktype:Int, hookname:String)
	If Not IsHookLoaded Then Return False
	ReleaseHook()
	HookProc = GetProcAddress( Handle, hookname)
	If HookProc Then
		CurrentHook = SetWindowsHookEx( hooktype, HookProc, Handle, 0)
		If CurrentHook <> 0 Then
			IsHooked = InitHookproc( CurrentHook)
			Return IsHooked
		EndIf
	EndIf
	Return False
EndFunction

Function ReleaseHook:Int()
	If Not IsHookLoaded Or Not IsHooked Then Return False
	UnhookWindowsHookEx( CurrentHook)
	IsHooked = False
	Return True
EndFunction

Function FreeHook:Int()
	If Not IsHookLoaded Then Return False
	ReleaseHook()
	FreeLibrary( Handle)
	IsHookLoaded = False
	Return True
EndFunction

test.bmx

SuperStrict

Import "Hook.bmx"

If LoadHook( "hook.dll") Then
	Print "Hook is loaded."
	If InitHook( WH_KEYBOARD_LL, "keyboard_hook") Then
		Notify "Hook is active, waiting for termination"		
	Else
		Print "error:InitHook() failed"
	EndIf
Else
	Print "error:LoadHook() failed"
EndIf
FreeHook()