Clicking on the gear icon in the toolbar or selecting Configure in the File menu brings up the configure dialog.
The configure dialog changes dynamically based on which program is currently running on Pixy2, but mostly the Tuning and Expert tabs change when switching programs.
The Tuning tab contains the parameters you are most likely to want to adjust when running a particular program. For example, when running the color connected components program, the signature ranges are in the Tuning tab, because these are commonly tweaked to improve the object detection accuracy.
The Expert tab contains the parameters that are less commonly adjusted but can still be important for a particular program to function at its best. For example, when running the color connected components program, the maximum number of blocks allowed are in the Expert tab because this is commonly changed once or twice and left alone.
Refer to the particular program references for what the Tuning and Expert tabs do for each program.