When taking the files to the standard main directory and applying the specified steps, an extra module that must be loaded during the first installation phase. It needs to be a file because it automatically drops to 500 error after doing Domain.com/Setup as standard.
The content of the error_log file of the 500 error I have experienced in the first installation should be done here on the server?
Can you kindly confirm that you commented out the first line of the ipconfig.php file as stated at the instructions at point 6 of the instructions?
Your error output points to a known issue that is solved in the upcoming version 1.6.1 and can also be solved by following the instructions as pointed out above.