You should have got the cardboard washers in the bag with the motherboard screws, iv never risked putting the motherboard screws in without them maybe someone else has and can answer that for you.
I'd forget about the cooler until you have the motherboard in securely.
I'd start with taking out the motherboard then take out the IO Guard.
Then try setup your stand-offs to the proper positions then try put your motherboard in again.
I'd forget about the cooler until you have the motherboard in securely.
I'd start with taking out the motherboard then take out the IO Guard.
Then try setup your stand-offs to the proper positions then try put your motherboard in again.