Video ScreenShare blocked by new version???

[MNnn]

I use an app called PowerDVD23 to show video clips [using an LG Slim Portable DVD writer/player, plugged into my Dell Latitude PC] as part of a lecture for an online course. This was working fine until the most recent Zoom update. Suddenly, the Screen Sharing interface is completely different and does not give me the option of sharing anything that isn't already online. When I try to share the video, with one setting the students could see it but hear no sound; or they could hear the sound with a black screen. Am I doing something wrong with the settings???