I am using Mocha Pro 2021 8.0.3 build 19 with Media Composer 2021.6 on a windows PC (2020 H2). I have a severe problem with the insert-tool. Within MC it does not render.
In detail: I have a moving car, and I want to change the license plate (for an exercise only!). Within MC the clip (transcoded to DNxHR SQ, no other effects) is on V2 and a static picture is in V1. Within Mocha I created a shape and surface and tracked it. I can now insert the mocha logo of something else on the license plate. Within Mocha that works fine with the logo and with the picture in V1. The car passes by and everything is ok. Save and quit.
Back to MC: Module Renders: Insert Composite, Insert layer None (or first belo). Now I can see the Mocha logo. I can go forward and backwards. Everything is ok. Now I hit the render button and rendering starts. Still I can see the Logo. When the rendering (takes one minute) has finished, the logo has disappeared.
Even worse with V1 instead of the logo: When trying to render, MC prepares a crash report and I have to kill MC.
Other modules (stabilize, remove) work fine, and so I think Mocha has a problem.