Apologies! Just to make sure I understand, you’d like to save your PCG that you setup in the scene, as an asset in editor. Is that correct?
If so, I’m uncertain the proper method for 5.4 and below, as it was intended in version 5.5 to be able to quickly save them to PCG Data assets as referenced here:
However the data assets were previously implemented so it may be possible to use them, though I could find no documentation on it. However, if it’s intended to be placed in the same location, you could save the seed itself instead, but that could change wildly if anything in the environment were to change.