Code Value Mapping does not save in CPI Mapping Guidelines

[AM7]

Hi,

I just created a Mapping Guideline in CPI B2B Addon using INVOIC IDOC Type for both target and source MIG. The goal is having a simple one-to-one mapping. 

I wanted to leverage the proposal functionality and it actually worked as it should, the best proposal gave me the desired one-to-one mapping.

However when I am saving the MAG, all the code value mappings (for example for DIRECT and OUTMOD fields in EDI_DC40 node) disappear. I can again select the best proposal which gives me all the mappings back, but as soon as I save they are gone.

What am I doing wrong? I just need a simple one-to-one mapping. Do I have to replace the code values with functions? But why is it not working this way?

You have any hints for me?

Thank you

Andreas