Hi Ixicalibur! Those wisps you see in the video are a secondary mesh emitter within the fog particle system. Since overlaying alphas are an extreme cost performance I removed them when I optimized my fog system. However they are still there! I have turned them back on and tweaked some settings, if you still want these please email me directly with this topic and I can share a new package with this setup with you.
Sorry for the delayed response!
-Brice