Hello again. I was aware of that issue as it bug me in my game too. But I wasn't sure how to fix it because it is inherent to the TilingSprite prototype of the rpg maker engine from which I built the plugin (If you put a parallaxe in the default map properties it will do the same if you shake the screen).
But you made me look into it again, and now I found how to fix it by enlarging the overlays sprite container and offset it a bit.
I'll upload a new version soon. But before that, I'll see what I can do for your previous request concerning the blending mode (if you still need it). Let's move this conversation on discord as it will be more convenient since I need some info about that request. Don't worry I'll reply, even though it may sometime take a few days.
You can contact me pm if you prefer.
Regards.