I recently came across two previously untranscribed (as far as I know) pieces of D'ni in Riven, from multiple sources. There are no new or unknown words in either of them, but I thought I'd share them here anyway in case anyone's interested.
The first one is the D'ni text that appears around the top of the link-in cage; I noticed a particular render of the cage which appeared in a Tumblr post by Yali (daggerlust), and which was apparently taken from Tony Davidson's website in 2003, that was just high-res enough that it's possible to tell exactly what it says.
[Reveal] Spoiler: images
The text on the render:

Also, for comparison, here are the two clearest images of the text in Riven:



Also, for comparison, here are the two clearest images of the text in Riven:


The second new transcription is of a phrase which appears around the base of some of the objects on Gehn's desk in Age 233. It was barely visible, let alone legible, in the original game, and the contrast of the higher-res version of the view of Gehn's desk which has been circulated for years isn't great, which obscures the text. Luckily, though, the recent the ART of CYAN PDF contained a much clearer high-res render of Gehn's desk, as well as another render of one of the objects with the text. Two of the images that Yali provided from Tony Davidson's website also showed the phrase, one of which was on the glass bottle, which doesn't have text on it in the final game. The clearest images of the text from these sources are as follows:
[Reveal] Spoiler: images
The two clearest instances of the text in the high-res image in the ART of CYAN:


The text on the object render in the ART of CYAN:

The text on an object render from Tony Davidson's website:

The text on an old render of the bottle, from Tony Davidson's website (note that it can also be seen through the bottle):



The text on the object render in the ART of CYAN:

The text on an object render from Tony Davidson's website:

The text on an old render of the bottle, from Tony Davidson's website (note that it can also be seen through the bottle):
