Hehe, I did it guys, yessss!!!:D I still have to create(or find) a decent light sprite, the one I have at the moment is just a stand in, but other then that I have achieved pretty much exactly what I wanted. I didn't even have to use clamp, the blend mode-source atop and adding another layer with force own texture was enough.
You can check how it turned here.
So thank you very much once again LittleStain , MadSpy .