Private Declare Function CreateWindowEx Lib "user32" Alias "CreateWindowExA" (ByVal dwExStyle As Long, ByVal lpClassName As String, ByVal lpWindowName As String, ByVal dwStyle As Long, ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hWndParent As Long, ByVal hMenu As Long, ByVal hInstance As Long, lpParam As Any) As Long
Private Declare Function ShowWindow Lib "user32" (ByVal hWnd As Long, ByVal nCmdShow As Long) As Long
Private Sub UserControl_MouseMove(Button As Integer, Shift As Integer, x As Single, y As Single)
' Aquí detectamos si el cursor del mouse está encima de la zona caliente
If x > 50 And x < 150 And y > 50 And y < 150 Then
' Aquí creamos y mostramos la ventana emergente
Dim hwnd As Long
hwnd = CreateWindowEx(0, "STATIC", "Mensaje de ayuda", WS_POPUP Or WS_BORDER Or SS_CENTER, x, y, 150, 50, UserControl.hWnd, 0, App.hInstance, ByVal 0&)
ShowWindow hwnd, SW_SHOWNA
End If
End Sub