please help me?

Hello; i must use last version cs-cart 1.3.4 sp2 but i take it mistake it?

1)before admin panel view order, status “open” change “backend” after i can see ticked “notify customer” and i make it update status; mistake bad gateway 502.

2)checkout shopping last step, Placing the order. Please be patient. and freeze but i can see admin panel it is ok shopping,but not remove cart. Maybe you can see mistake picture and help me?

Danger= My server windows and panel plesk 7.6.1

what gateway are you using?