Post feature image changing depending theme

Hello i have a theme from rockettheme with many presets and i also use a widget on the front page that uses image posts with custom fields. So if i change the preset style the images would change automatically( images i create by myself at a earlier time)

What i need to do to achive that? What plugins or code modifications do i need to make?

Or an alternative is to make posts for every preset and show them only on that particular preset. Is this possible?

Take a look at: http://www.net-flux.com

Thank you