Corner shape
Open Design > Template, then click Customize Look. In the Top Banner section, find the Corners control. Four options: Default (template's built-in rounding), Sharp (no radius — square corners), Soft (subtle rounding), and Round (fully rounded, pill-shaped). The setting applies to both the form card and the CTA buttons.
Button labels
To customise what the buttons say, go to the Build tab and click Form Settings at the bottom of the step list. Open the General tab and expand Button Text. You can set individual labels for: the first-step button (optional — hidden by default), the Continue button on middle steps, the Get Results button, and the final Submit button.
Button colour
Button colour is the brand colour set in Design > Theme > Colors. There is no per-button colour override — all CTA buttons use the same primary colour.