It just seems to me that the guy was a persistent and obviously very talented engineer. Before calling into question the paranormal, I'd first call into question the assertions that this was all done without the aid of any type of motors or other mechanical lifting equipment. That would appear...
Engineering feat
Judging by a pic taken from their site, it may be a marvel of engineering but certainly not anything paranormal.
http://www.coralcastle.com/photos/edatwork1.jpg