Hmm...

[Ambientiger]

I was having a little think about this at work today, do you need the movement only to execute when the label is showing.
If not, I would seperate out If statement that checks if LblMenu is visible, like this;

Code:

If MouseCheck = True Then
       If Button = 2 Then
            XToGo = (X + (NewPlayerX * PIC_X)) / PIC_X
            YToGo = (Y + (NewPlayerY * PIC_Y)) / PIC_Y
            Call CheckMapGetItem
            If LblMenu.Visible = True Then
                LblMenu.Visible = False
            Else
                LblMenu.Visible = True
            End If
        End If
    End If

In theory this should cause LblMenu to appear at the place it is on your Piscreen picbox on a right click, then disappear again on the next click.