Hello,
Thanks for this demonstration
In this example it works, but what if you try to put the layer at z-1 (like water parallax) do you have the blinking issue ?
Ok, sorry I could not help much, but I need to reproduce the problem first before I can investigate what is happening. You could try some kind of preloader for your water layer graphic or whatever it is that blinks. It could just be that the plugin is struggling to load it in time when it also has to load mirror sprite + light sprites, I am not sure.