I haven't got much on that accident not having been personally involved, I know the accident was to EH101 prototype PP4 on 7 April 1995. That should get you started, back copies of "Rotor and Wing" or "Flight" might carry some technical discussion. I also recall an interesting write-up in "Feedback", which is the MoD flight test / flight safety magazine, but I don't have routine access to that and you might struggle unless you are able to access a military library.
I doubt somehow you'll find much on the net, good old fashioned libraries still have their place
By the way, have you looked in CS.25 and CAA LAMS, both documents should contain some useful reference material. Also look at FAA AC43-14 possibly their guidance on quick build aircraft kits, the composite construction QA stuff in there is very thorough.
G