Hi @ebeltran
Thank you for confirming!
By any chance, are you using the Classic Universal login? The signup-password form will only work with the New Universal Login, as Classic will ignore the prompt and not render it.
In addition, please double-check in case the partial exceeds the 10,000 character limit, as it could also be a reason for rendition failure. Can you try setting something very basic in the partial just to see if that gets rendered, which could indicate an issue with your full rendition that can then be figured out.
Looking forward to hearing how it goes!
Gerald