The last column has the debug output of the compressed file when you say "y" to debugging
WARNING: Do not copy and paste the contents of the txt files, you will run into weird bugs. Right click and press "Save As" to download the file
Remember that in jGRASP you can use a structure viewer to see what your tree looks like. You do so by dragging one of your fields from the debug window outside the window and jGRASP will launch a viewer. This viewer will show you the structure of the tree, but may not show you the contents of the nodes. You can fix this by selecting the wrench icon ("Configure the structure to view mapping"). Under "Value Expressions" say:
Where "<field>" is the name of the field you want to view. You can also say:
Helpful diagrams: Your jGRASP debugger won't look exaclty like this, but the characters, frequencies, and positions of nodes in the tree should match.