Is it an older Swiftech MCR320 with 3/8 NPT threading or is it a newer model with 1/4 NPSM?
If it's the older model, it might *possibly* from trying to use G1/4 fittings on 3/8 NPT.
If it's a newer one with 1/4 NPSM... I don't know
I have an inbuilt res on my DDC-2 top. I have a ball-valve on the G1/4 fill port at the top, so I just leave enough slack in both the inlet and outlet line to be able to flip it around and drain the loop.
Well you need to jump the green and black wire on the 24-pin mobo connector to hotwire the PSU. Therefore, if you are running a pump powered by the PSU, it will shut on and off with the rest of the system.
Don't be afraid to ask (as long as you read similar threads and use the search function first)!
Key to successfully setting up a loop is going nice and slow. Every time I rush, I end up with a mess everywhere.
As for worrying about things going wrong, it took me a long time to push the...
I'm assuming two 120.1's? ("2. 120" is a little ambiguous for me)
First case that came to mind for me was Antec P180. One at the back, one at the 120mm fan hole in front of the top hard drive cage (remove cage though)
Whether condensation forms depends on what the ambient temperature is compared to the block temperature (or whatever), and what the relative humidity is. If the surface you're worried about condensation forming is at a higher temperature than dewpoint, no condensation forms.
Mine came with screws (enough for just one side, for non-flanged fans)
M3.5 if I recall correctly
As for figuring out what length to buy, just stack a fan on top of the rad, and measure with a ruler.