UDL - just stops working mid game

This started happening when I was playing in a game - the explorer mode was working, but not the actual lighting. I could see all the places I had been in the map, but everything was dim. I told the DM to use the legacy lighting "Cause it actually works" - they used legacy, and everything was fine.  Then I got the notification that the Updated dynamic lighting was fixed and Roll20 was retiring the legacy.  I decided to update one of my games to test it. Sure enough - it doesn't work. It worked for a while, then out of nowhere, my players suddenly lose their sight; they can still see everything from explorer mode dimmed - they can see their tokens - just not everything else.  We tried to troubleshoot for a while, which just ended up in my players seeing the entire map. Everything I did, the Dynamic lighting would suddenly work, but as soon as the players moved their tokens, everything would go black.  I had to go back to legacy lighting again.... 1) Does anyone know why this happens? How to fix it?  2) Roll20 - please don't retire the legacy lighting... it actually works

A similar thing happened to me last week. About halfway through my game the UDL stopped working for my players. What is even more weird, all my lights on my map (torches, fires etc) seemed to throw out darkness rather than light, and my players couldn't see anywhere that was illuminated. Apart from one player, who managed to see the entire map all of a sudden. Had to abandon the game. When playing around after the game I managed to get things working again by toggling the UDL darkvision setting for each character token off and on again, though it still threw up strange effects now and again. Still some game-breaking bugs in there I'm afraid!