Coming Soon seems to work fine for the Altrium files, though I’m not sure if you can extract any useful info that way. I just uploaded the zip file.
I seriously doubt the holes are for heat sinks. The original board was going to be fanless until we managed to melt a chip during stress testing. I would guess something along the lines of alignment holes for equipment used to mount the processor on the board.
Replacing the fan is easy. The make and model has been mentioned here before. See for instance