Black screen when loading a game with a mod

[Szizorillo]

I've put the Data folder in atmosphere/contents/<TitleID>/romfs/ but I just get a black screen and nothing happens when I attempt to boot the game -

• contents/
  • <Title ID>/
    • romfs/
      • Data/
        • StreamingAssets/
          • AssetAssistant/
            • Pml/
              • personal_masterdatas

I tried a more simple mod (no intro videos) and this seemed to work so I'm not sure what's going wrong.
atmosphere/

• contents/
  • <Title ID>/
    • romfs/
      • Data/
        • StreamingAssets/
          • Movie/

So any mod that modifies the "AssetAssistant" fails for me. This is the first time I've ever tried any mod stuff so I'm trying to figure this out from fresh basically. Any advice? Any settings or config files I need to change? Thanks!

Btw I migrated from SXOS to atmosphere i dont know if this is relevant