To import the project into Eclipse IDE:
Open the menu 'File->Import...'.
From the 'General' options folder, select 'Existing Projects into Workspace' and click on the 'Next >' button.
Choose the 'Select archive file:' option and next to it click on the 'Browse...' button to navigate to the project archive (ending in '.tgz') you downloaded.
The project name will appear below - click on 'Finish'.
The project will be imported and opened in your Eclipse workspace.
For command-line users:
Please note that to run the application successfully outside of the Eclipse IDE environment (e.g. from a 'make' within the "../Debug/" directory) the GUI file "gtk_gl_tester.gtk" must reside in the same directory as the compiled binary for it to run.