After struggling with getting a blank screen during the final installation process, I found a note in another post regarding raising the memory_limit in php.ini. In MAMP it is set to 8MB by default so I raised it to 64MB and it worked fine.
So if you get a blank screen while installing check your memory_limit.
Note: in MAMP-Pro you can edit this by selecting File > Edit Template and then selecting the template for the version of php that you are using. Look for memory_limit = 8M and change it to memory_limit = 64M (or higher if you want) and restart the server.
In standard MAMP you need to edit the php.ini file itself.