Well after a hectic start here are the answers to Round 1
Question 1:
Inquisition- The Holy Orders of the Emperor's Inquisition were founded after which cataclysmic war?
The Horus Heresy Question 2:
Imperial Guard- Which type of large, often stupid abhuman is often fielded as assault troops by the Imperial Guard?
Ogryns Question 3:
Space Marines- Which Predator variant is armed with a turret mounted autocannon?
A Predator Destructor Question 4:
Tyranids- On which planet were the Tyranids first encountered by the Imperium?
Tyran Question 5:
Horus Heresy- At which battle of the Heresy did Khârn suffer a wound that almost killed him?
The Battle of Terra Question 6:
Eldar- Which Craftworld was nearly destroyed by an element of Hive Fleet Kraken?
Iyanden Question 7:
Chaos Space Marines- How many points are there on a Chaos Star?
8 Question 8:
Imperium- What title is given to the head of the Adeptus Ministorum?
Ecclesiarch Question 9:
Necrons- Which Necron troop type clothes itself in the skins of their enemies?
Flayed Ones Question 10:
History of the Imperium- Which Inquisitor was admitted inside the fabled Black Library and subsequently became the most prominent Imperial authority on the Eldar race?
Inquisitor Czevak
Question 11:
Orks- What name is given to Orks who scrape together enough wealth to buy themselves the best, most outrageously destructive kustomised guns they can carry?
Flash Gitz Question 12:
Famous Battles- How many Armageddon Wars have there been?
3 Question 13:
Alien & Chaos Vehicles- Whch fast, open-topped vehicle is the most common transport in a Dark Eldar army?
The Raider Question 14:
Khorne- What does the throne of Khorne sit upon?
A mountain of skulls Question 15:
Tau- By what three letters and digits is the Crisis battlesuit also known?
XV8 Question 16:
Imperial Vehicles- The Imperial Guard Basilisk is based on the chassis of which vehicle?
The Chimera Question 17:
Imperial Navy- What is the name of the psychic beacon used by Imperial ships to navigate their way?
The Astronomicon Question 18:
Weapons- The Vanquisher is a variant of which tank with an elongated battle cannon?
The Leman Russ Question 19:
Random- Finish the quote- 'Hope is the beginning of _________'
Unhappiness Question 20:
Random- What will 'Your Courage, Your Loyalty, Your Resolution' bring?
Victory
The questions that caused the most people problems were (by a large margin) Questions 19 & 20- many answers ended up being extremely similar with Despair and Salvation respectively ending up as the most common incorrect responses (though a rather jammy Mr Berenyi managed to answer Q.20 correctly by taking a random guess).
Close behind the quotes was Q.10 which ended up with me getting a lot of different Inquisitors as the answer 
----------------------------------------------------
Here is the list of people who have managed to qualify for Round 2 and their scores, my regrets to those of you haven't gotten through but try and taken comfort in the fact this won't be the last Quiz Competition:
experiment 626- 20/20
Warmaster Romulas- 19/20 (completed Round 2)
Lord Marcus- 18/20 (completed Round 2)
Rhaalidor- 18/20 (completed Round 2)
Stubber- 17/20 (completed Round 2)
Dead_Commando- 17/20 (completed Round 2)
Templar Mikeel- 17/20 (completed Round 2)
Heroka Vendile- 17/20 (completed Round 2)
Drax- 16/20
Baron von Lexus- 16/20 (completed Round 2)
Sir_Servo- 16/20 (completed Round 2)
Spartan_11755- 16/20 (completed Round 2)
Four20edLogan- 15/20 (completed Round 2)