Double click on a button object in Preview window or in Timeline to open a Button Properties Window.
For a Submit button belong to a quiz object, there will not be a timing and duration control but for a button you insert from Insert menu, there will be a timing and duration control you can use to adjust when and how long the button will show on the slide.
Font settings
At the top of the window you will see the common text settings control such as Font, size, bold, italic, underline, alignment and color.
Alpha
To set the text transparency. 100% is a completely transparent.
Button text
To type in the button text
#PAGE# = To insert the page number
#QUESTION_NUMBER# = To insert the current quiz number. Eg: The first quiz will have QUESTION_NUMBER = 1, the second quiz will be 2, etc.
Button type
Click Change button to choose a button type.
Background color
To choose a button background color
Border color
To choose a button border color
Apply font and button style to other buttons
When checked, clicking OK button will apply the changes to font settings and button style above to all button objects within the presentation.