Cadphan 504 module calculating MTF


I was wondering if there is a bug in the calculation model for the calculation of the MTF (lp/mm) resolution.

In the cadphan 504 manual there are only line pairs per cm, however the mtf is calculated as lp/mm. Is this correct?
Im trying to derive a lp/cm value that corresponds to the lp/pair seen in the phantom. But sometimes this gives me strange results.
i’m calculating the mtf for a given % lets say 50% this gives me a value of 0.52 lp/mm.
from the results dictionary this value coresponds with region 5. is this a valid way of calculating the lp/cm region seen as described in the 504 phantom manual?

And,is there a way to plot the cirkle profile?

hope you can help me