Hi John,
I hope you are well today and thank you for your question.
You can set the break between appointments by configuring the Break Hours for the service provider on the following path.
Admin Area -> Appointments -> Settings -> Working Hours
If you want to add padding times surrounding your appointment interval then you have to use the Paddings appointment add-on which is only available in the following pro version of appointments plugin.
https://premium.wpmudev.org/project/appointments-plus/
You can change the colors of Busy and Free cells of appointment calender from the following path.
Admin Area -> Appointments -> Settings -> General -> Display Settings -> Color Set
If you want to change the text color of Busy and Free cells then please share me the page URL from your site where you displaying the appointment so that i can provide you custom CSS solution to change it.
Please advise if you have more questions.
Best Regards,
Vinod Dalvi
