Compositor + Caelum Issues

Ok, so, Im trying to get my heat wave shader http://www.ogre3d.org/forums/viewtopic.php?f=2&t=51092 to work with Caelum but Im running into issues.

What Ive done so far:

In the Frame Listener's frame started function, I have:
mCaelumSystem->updateSubcomponents(evt.timeSinceLastFrame);
mCaelumSystem->notifyCameraChanged(mSceneMgr->getCamera("PlayerCam"));

In the createscene function:
//sky
mCaelumSystem = new Caelum::CaelumSystem (mRoot->getSingletonPtr(), mSceneMgr, Caelum::CaelumSystem::CaelumComponent::CAELUM_COMPONENTS_NONE);
Caelum::CaelumPlugin::getSingleton().loadCaelumSystemFromScript(mCaelumSystem, "DefaultSky");
mCaelumSystem->attachViewport(mSceneMgr->getCamera("PlayerCam")->getViewport());
mCaelumSystem->setAutoNotifyCameraChanged(false);


Caelum is not rendering information onto the heat wave RTT, so its not interfering wit that, but, I cant even describe what it looks like its doing. (note: the gray area is where the ogre head is supposed to be, the little flakes are the particles used for heat, seems that they render on just fine.)


My question is simple: What am I missing?

Ok, I had everything set up right, but it turns out the shaders lerp function somehow commits graphical manslaughter when used with Caelum. Removed lerp, started working normaly. (Although I notice my shader doesnt want to distort the sky of Caelum still)