Hello Dariusz,
we did not change much in the VRED exporter python script. The last update that you should see in 5.5. is that you now have two versions, the old one and one with some library changes and cleaning because Autodesk changed the Python version they were using and old script was not working anymore. From what you said it is some of the fix you also did on your side.
Since you managed to change the code in UE to have better naming, do you mind sharing the new python file with us so I have a look.
Thanks.