Indeed, they don't allow to monetize the content created, which is a bit odd. You use their software and your content, not theirs. The software helps you create based on your content. However, try using another application instead. For example, install and use Gimp. It's the open source version of Photoshop. You can do whatever you like with the content created in the application and avoid using or installing Photoscape in the future.
Gimp download: http://www.gimp.org/downloads/