Hi,
Ive uploaded a new file through the link you provided.
I really feel this is a typical example where motionblur should have worked. The tyflow configuration has been tailor made for corona acceptance criteria - no change in topology, still it hangs at "Transforming Vertices".
1. All particles are simple spheres.
2. There are no particles birthed / killed during the entire animation (no change in topology)
3. Particles are scaled to zero instead of killing them - so they are still in the scene, just infinitely small.
4. All particles are birthed at the same frame (frame 0) (the animation is reverse direction so they are all actually birthed at frame 500, just playback is in reverse).