Corner Pin probleme export

You may simply need to pre-compose some of your hardware accelerated effects steps. Using all that Red Giant stuff could easily cause all sorts of weird issues on top of AE's own poor hardware acceleration.

Mylenium

The tutorial uses Mocha Pro. Did you use Mocha Pro? Screenshots that don't show us the modified properties of the problem layers do not help diagnose problems. We need to see what is going on in the layer. On an English installation if you press the "u" key twice it will show all modified properties of a layer. Check your French keyboard shortcuts. 

Also, please embed the screenshots instead of using the Drag and Drop here area. It's buggy and hard to use. You can drag images directly to the reply field or use the Toolbar to embed them. 

I would give that tutorial a C-. It does a pretty poor job of explaining the workflow and offers nothing in the way of the why.

If we knew what was fouled up in the comp by looking at the modified properties of the layer we would have a better chance of helping you solve the problem.