well i'd just like to post this little tidbit somewhere, doubt it'll be seen by many. I was struggling with getting any bounce to work for days and when i finally got it the collision was non existent.
at last I found out that NMM, or even WinRAR for that matter, was not extracting "hdtPhysicsExtensions.dll" from the HDTPE mod archive. I had to manually extract it to my desktop and then move it to the correct folder (data/skse/plugins).
but that one stupid thing fixed everything! now HDTPE AND HDT TBBP work, among other HDT mods!