https://guildofwriters.org/wiki/RAWA%27 ... or_Writing
The "revised five rules" section says:
When Writers (aka fan developers) are creating linking books they are bound by the D'ni limitations of writing. However, Writers are able to use special items for linking and modifications to linking with the following limitations: Writers should stay away from special Cyan created character items (such as Yeesha and Bahro items) with the exception of Yeesha Pages (bring a piece of your Age into the explorer's Relto!).
But the "further clarification" section says:
One question, if we are not allowed any of yeesha's "powers", does that mean we cannot make relto pages?
A: SCGreyWolf is correct. Yeesha's Relto pages are off limits. Other collectibles would not be off limits, though the guidelines for props, clothing, etc. do not exist yet, either.
Was that latter section simply not updated after the revised rules were created? I thought it would be cool if there was an Age where maybe the pattern on some local fauna/flora might be the solution to a puzzle, but a journal would reveal that species had gone extinct, but then you find a Relto page that adds that species of plant or lizard or butterly or whatever to your Relto. I don't remember Relto pages ever being incorporated into puzzles.