What does the fault code mean ?

[Mikee5]

Hi guys,

I have recently purchased a 2009 X5 E70 4.8i.
The Check Engine Light has since come on with error codes
29f4 & 2D32.
I looked them up and found their "definitions", then did some searching on google and this forum, which led me to believe I had a vacuum leak (2D32)which was probably causing the car to run rich and fouling a catalytic converter (29f4).
I went searching for leaks and found tube from the MAF to the Throttle body was incorrectly attached and leaking and that the CCV assembly had been butchered by a ham fisted repairer in the past, and was passing engine oil into the inlet manifold, which was then blowing out as smoke in the exhaust
probably further fouling the cats.
I have ordered a new CCV assembly and a new inlet tube, both are currently sealed up with silicon sealant till their replacement are installed. CCV is working sort of.
I cleared the codes and took the car for a drive and the error lights stayed off. All of this leads me to my questions:-
1) How often does the car look for error codes, as the CEL has not come back on and
2) What does "Error not currently present" mean? I rescanned the car both codes came back, 29F4 is there as a current fault, I expected it to be there at least till the oil clears out. 2D32 shows not as a current fault but as " not currently present" is it just a historical listing or something else?

Any help would be appreciated,

Thanks
Mike