Finding hotspot tutorial related issue

As per the Tutorial: Finding Hotspot, I could Build application and create new project, Run Basic Hotspots Analysis, Interpret Result Data. But while trying to Analyze Code and edit the most hotspot region of the code, I was unable to open the editor from Open Source File Editor icon. It was showing "Cannot Open the external text file editor for this file."

I had also given $ "export EDITOR=gedit"  command in the terminal before running amplexe-gui. Kindly help me with the issue and suggest me how to get access to the editor.

Thank You.