Editor 7 includes an image editor so you can make changes to images
Open the image editor
Click the images tab (1). Move your mouse over any image (don't click, just hover) and you will see some icons. The paintbrush icon (2) will open the image editor.
Using the image editor
Select an image edit mode (1). Click the save button (2) when you are finished.
Adding the new image to your page
Everytime you save an image, a new version is created and this will appear in the top of the images tab (1). Drag and drop this onto your page to use it.