I got the following syntax error when I first open the site for installation: "Parse error: syntax error, unexpected ':' in .../install/index.php on line 145"

I fixed it by changing "return $error ?: true;" to "return $error ? false : true;" in .../install/index.php on line 145. I got the Installation Wizard after doing this fix.

Please look into it and confirm what I have done is correct and also update your files in downloads.