shockwave particle with refraction "breaking" UE4

Hi,
I’m trying to make a shockwave just when a energy ball explodes.

This shockwave is made out of a mesh emitter (sphere) that quickly expands with a refraction (glass material with a water normal map on it) material on it
to simulate hot air that distorts everything.
But some weird stuff is hapening and it’s not working at all.

So this is my scene with on top of the tower an energy bal and some vector field GPU particle that is about to explode.
At that spot i’m also emitting a mesh (sphere) with a material on it with refraction that is supposed to look like a shockwave,
but it’s just flashing weird colored shapes. This happens in cascade and in the viewport. (material is on the right)
31dc03d448b4940d34a18cdfb438267dde41534c.jpeg
b2f25d2edb860d067dc24f58166d7aaaa4fab6af.jpeg

This is what it looks like when i just put it on a mesh (NOT particle).
5c68a287df2ac7f81e74196a39b7cb9973da6988.jpeg

This video has an excellent example of what i want for my shockwave, you can only see it in 2 frames or something so look carefully.

Really weird,
but I made a waterfall particle a while back, just a normal emitter (sprite emitter i guess?), with almost exactly the same material.
That particle just has some extra water texture in the base color and it works fine.

Solved it!
this is the material now: