Hey Willy great diagrams they are great way to visualise , i did the same. What i'l do is the same and monitor the intake hose. I'm going with a HKS S/C.
How is your CC setup running has it collected anything? Your motor is built so i imagine its running without any or much blow by.
Was the valve the right diameter for the 3/8 hose you used? Just as a side note Nissan Australia quoted me $66.00 for the check valve! Thats gouging!!!