Diagnostic Level

Raise this number to get more diagnostics.
Lower it to get fewer diagnostics.
Set it to 0 to eliminate the diagnostics.

If you set the diagnostic level greater than 0, a 0 data axis will be drawn on the track.

If you set it greater than 3, the coordinates of your pick will be displayed.

In general, a non-zero diagnostic will print out more information if there is an error.