About your questions about Armageddon with LGA775, please find the answers as below.
1. Yes, you need the (Intel) LGA 775 Backplate Spacer to mount the Armageddon on a LGA775 motherboard.
2. (Intel)Spring loaded screw of Megahalems Rev C is the same as Armargeddon. However, the spring loaded screw, which Frozencpu sell is for Megahalems Rev B.
What you need is Megahalems Rev C's spring loaded screw which is same as Armageddon's spring loaded screw.
There are some differences between Megahalems Rev B and Rev C.
I. Rev B : contains Intel mounting kit only, Rev C : contains Intel and AMD mounting kit
II. Rev B contains longer (Intel) spring loaded screw; however, Rev C contains shorter (Intel) spring loaded screw. In addition, Rev B and Rev C have different Aluminum Mounting Plate.
Because Rev B and Rev C have different Intel mounting kit, Rev B can mount 120mm fan only but Rev C can mount both 120mm and 140mm fan.
http://www.prolimatech.com/en/products/detail.asp?id=887&subid=948#showtab
We'll update the differences of Rev B and Rev C on our website soon.
So you need the (Intel)LGA 775 backplate spacer and the (Intel) spring loaded screw (the shorter one) for Armageddon.
We can send you the spacer and the spring loaded screw as our customer service to you.
Please offer us with your shipping address. And it normally takes around 10-14 days to ship goods from Taiwan to foreign country via registered airmail.