Hello!
It looks like all your messages are about the same 5.2 upgrade problem, so I've moved them into a single forum thread.
In case you face the same issue, please sign into your account at
https://secure.x-cart.com/, create a ticket there, attach your log files (that you can find in the [xc5]/var/log/ directory) and let us have the access to your server (if possible).
Also, if you created a backup, please let us have it so that we could try upgrading your site on our computers locally.