How to upgrade web2pay module from 1.4.7 to 1.4.8?

Hello.

I've web2pay payment module. But it's made for 1.4.7 opencart version.

When i try to use it in 1.4.8 version it just doesn't activate. When i press edit and change any settings and try to save them i'm just forwarded to dashboard page.

I believe it's because of new version incompability. I've tried to upgrade module using this tutorial (http://forum.opencart.com/viewtopic.php?f=22&t=15875) but nothing changed. Maybe i did something wrong.

Could you take a look at this. File attached. Thanks in advance.

Package fixed for OpenCart v1.5.1.3.