Edit function generate blank page

[eluser]patak[/eluser]
Hi all!
I totally got stuck with one of my controller.
I am developing e-shop system for selling wine and my edit function after submitting “generate” blank page.
The edit function normally load data from database and send them to view with form. When I submit the form I get only blank page and I really understand why. I am using similar function in other controllers and it works great.
Unfortunately the function is to long to post it here so I have attached it also view the file.
If someone look into my files and try to help, I will be very happy!
Jan