ah - just realised the flaw in my cunning plan ... to get to the timer on-screen menu, you need to use the camera hardware button (double "half-click") - you said your button only works "if you click it hardly" - that is a bit unclear but sounds like you may have trouble doing the "half-click" action (the one which normally is used to focus before taking the picture).

If so, you could still ask the developer if he can provide a fully touchscreen activated method of selecting the timer function though? sorry for the bum steer :-(