1.5.3 - Products form not available

[GSheelm]

My problems are:

 

1. I have installed the 1.5.3 and I've backed up the database (1.5.2).

 

After doing this, I can see the products, but I can't use the menu buttons, like prices, SEO etc.

 

2. At CSV import:

 

Reloading the filled file from the downloaded example file, I've got the following error message:

The character code is not suitable. I use UTF 8 at the database, with Hungarian accents.

How can I download the products fast and easy with accents?

 

3. Png pictures

 

Where can I reach the Prestashop's png pictures? I'd like to change the background at the default theme. I'd like to avoid the jpg pictures' white background.