Rich Text Splines Tutorial? - Actually a BUG

I can't find anything via Google on how to use Rich Text Splines - probably because I'm using the wrong terminology.
Can someone point me in the right direction for an Online Tutorial on this? (see attached image):
Thanks!!

I've been tearing my hair out trying to use the Rich Text Splines with markers for X and Y Positions in the Edit window, but markers don't show up and when I click on the item in the Rich Tech Inspector, the whole line disappears!
But when I try the same with with the Zoom control, the splines and markes appear and I can modify them.
So it appears to be broke in DaVinci Resolve.

P.S. This is like the 6th posting I've made on Resolve and none have every gotten any responses. Am I persona non-grata?