Preferences

Choose Edit → Preferences.... The dialog is Edit Preferences. It sets the zodiac, the house system, and which aspects are calculated. Choose Save Preferences to keep them. If a chart is already on screen, it is drawn again. Cancel discards the dialog.

Zodiac type

Zodiac Type is Tropical or Sidereal.

Tropical measures the signs from the March equinox, so 0° Aries stays tied to the seasons. Sidereal measures them from the stars, so the sign boundaries sit in a different place against the same planets.

House system

House System is how the twelve houses are cut. Placidus is the starting choice. The menu also includes Koch, Whole Sign, equal, Campanus, Regiomontanus, Morinus, Porphyry, Alcabitius, and the other systems in that list.

Porphyry and Whole Sign each appear twice. Those entries are separate systems that share a label.

Saving a house system here also sets House System in Enter birth data.

Enabled aspects

Enabled Aspects is the same set as Visible aspects on the chart: Conjunction, Opposition, Trine, Sextile, Square, and Quintile. The orb is the degrees of slack that still count.

All, Major, and None match the buttons on the chart. Major leaves Quintile off.

You can change the same switches on the chart without opening this dialog. That change is saved immediately and the chart is drawn again.