MIMOLIVE 4 Background Layer does not convert correctly.
ML 3 -> converted to ML 4, the background layer doesn't convert properly. Instead of showing the configured background video (set to loop) it shows a transparent background. If you re-select the video from the Source dropdown it correctly displays for that session, but if you reload the document (even after saving) the background layer goes back to showing a transparent source instead of the configured video.
You have to delete the background layer and re-add it with the video source, which then works across sessions.
TLDR conversion of ML3 background layer to ML4 backround layer is not working.