You could run a virtual machine (like Parallels or VMware) with OS X Mountain Lion installed. Then, inside that virtual machine, you could install your legitimate copy of SketchBook Designer 2013. However, this kills performance and is hardly "free" (virtualization software costs money).
SketchBook Designer 2013 was surprisingly light. It could run smoothly on a 2013 MacBook Air with 4GB of RAM. Modern creative software (like Fresco or Illustrator) demands 8-16GB and constant internet connections. autodesk sketchbook designer 2013 mac osx free
Below is an overview of the software's history, its current status, and where to find modern, officially supported alternatives. 1. The Legacy of SketchBook Designer 2013 You could run a virtual machine (like Parallels
It is crucial to distinguish from the standard SketchBook Pro . inside that virtual machine