Hi!
I've got news for you. My mechanic is a bit busy and couldn't work on my car until next week, BUT I had a couple hours alone today so I decided to give it a try.
Well, the actuator was actually easier to replace than I thought, it only requires a bit of patience and focus. Having the new part on the side helps to understand how all the things are connected
It took about 45 minutes to do all the work (the door panel was already removed) and now it works just fine!
Thank you so much for all the help!