Maybe your memory limit is set too low and your site is out of memory. Check the BPS System Info page – PHP Actual Configuration Memory Limit. If your Memory Limit is less than 128M then contact your Host and have them increase the memory limit to at least 128M.
Do these steps for all the other issues:
1. Turn Off AutoRestore.
2. Edit your wp-config.php file and fix this problem: Constant ABSPATH already defined in /home/xxxxx/public_html/wp-config.php on line 52. Look at line 52 in your wp-config.php file and fix whatever that problem is.
3. Go to the Setup Wizard Options Tab page. cURL Scan Option: Turn On|Off cURL Scan – set this option to: Turn Off cURL Scan and click the Save cURL|DB Monitor Options button.
4. Run the Pre-installation Wizard and then the Setup Wizard.