I'm using the medium Small-E icons/theme in Winterboard. I have a 3G v 2.2.1.

I want to resize these 3rd party app icons:
Category icons (games, apps, Nav, 3rd Party, fitness),
Easy Button, file2mail and a bookmark shortcut on the homescreen.

However, when I go into winscp to applications/theme.app/icon.png and try to open it to edit in Paint.Net, I get an error message. What am I doing wrong?

I followed a tutorial I found, only they were using another editing program.

Thanks in advance.