Making things react
Variables (Screen & project tab) are the glue. Bars, counters, sliders, switches and selectors read and write them.
Write {gold} in any text to show a variable.
Actions run when an element is clicked or changed: go to a screen, open a popup, switch a tab, change a variable, show a toast or recolour the theme.
Show only when hides an element until a condition is true, like a warning when hp < 30.
Hotkey fires an element's actions from the keyboard in Play, e.g. Escape for a pause menu.