Okay, so I got it to unfreeze by randomly clicking the screen, but dialogue doesn't show and I have know clue what happens in the end
mmmh ... yep that helps. Suddenly, it must be your processor that takes care of the graphics part. Actually, I'm curious about the limit of VRAM you have, can you tell me the reference of your processor?
It is true that this particular scene is the one that has the most images at the same time. Maybe i could split the scene into two scenes, but since i don't know the limit, i don't know if that will be enough. It might help me to set limit for later.