I understand the new Session Player should allow me to overlay the MPA gauge on top of Zwift, but for some reason I cannot get it transparent. The background is solid black. Tried both Embedded and Overlay layout, and tried different transparency settings, but still black.
Windows 10 with Google Chrome. Any ideas ?
Transparent overlay option is for when you are streaming within the Session Player.
For that you need to create a session with a YT video link defined under the Media tab then open the Session Player.
Example: https://forum.xertonline.com/uploads/default/original/2X/c/cad1241e4d2d8f270f1aea1dd9a69c2dc70069d3.jpeg
If you have a large monitor you can overlay the Zwift app on top of the Session Player with Zwift covering the video block section. Or with dual monitors you can drag the boxes you want on top of Zwift with HUD disabled. No transparent overlays but it gets the job done. 
Example: Redirecting...
The only way the Player could work the way you want is by using OSB.
Thanks for clarifying this. I like my zwift to take up the whole screen, so guess I’m out of luck then.
